3800 swap harnesses
Topic started by: FIEROFLYER, Date: 11-17-2007 09:49 AM
Original thread: http://www.fiero.nl/forum/Forum9/HTML/000026.html


FIEROFLYER MSG #1, 11-17-2007 09:49 AM
      I am finally caught up on my harnes building so first my appologies to those who have had to wait all harnesses will be going out first thing Monday morning. Second is I made a promise a while ago to do a build thread on a 3800SC swap harness and I now finally have the time to do it.
What I would like to do is have some input on what options to run on this harness for example is it for a manual or auto swap and should emissions be kept or removed. I ask this because this harness is an extra that will be auctioned off when finished and all the money going to PFF the purchaser will need to pay Cliff not me. Not quite sure how to auction it off so a little help there would be appreciated.
The harness build first remove the complete engine harness from the donor 3800SC engine. I have hooks on my garage door that I use to hang harnesses on for stripping.




Next is to remove all the loom and tape from the harness, you will find on some that the wires all stick together which will require some extra work to pull them all apart.



These are a few connectors from the harness that can be cut off to free up the wires, they are the main firewall connector and the connectors for the ABS sensors and others for feeding wires into the car.







Next I remove carefully each pin from both PCM connectors, this is done by first removing the plastic covers then gently bending back the clip above the pin and lift the pin slightly then pull the pin back out of the connector by the wire.






With all the pins removed from the PCM connector I now seperate all the wiring from the harness and set aside each sensor connector with its wiring.




And of course save all the removed loom for sealing up the harness once assembled. A good idea is to go to a wreckers and remove extra loom from other cars as you will need more loom to finish off the harness.





Now I will pull out one of my spare engines to start reassembling the harness. At this point input would be nice on which tranny to make this harness up for the 4T65E HD that comes with the 3800SC engine or one of the manual trannies that come with the Fiero. Dan




BoostedSeries1 MSG #2, 11-17-2007 11:45 AM
      I would like to see it done with a manual tranny. If that will be the one chosen I would say to make it for the getrag. Though it would not be much diff. for the other manuals

FastFieros (fastfieros@fastfieros.com) MSG #3, 11-17-2007 12:53 PM
      I would say do an automatic, and then along the way make **NOTE** remove this plug for manual... Change VSS here to longer for VSS on GETRAG.. like that...

Loyde


multmigs (multmigs@verizon.net) MSG #4, 11-17-2007 01:19 PM
      I've looked at alot of swaps and I vote for the 4t65eHD that's the trans it mostly came with and seems like it would be more complicated than doing a manual trans...

FIEROFLYER MSG #5, 11-17-2007 01:34 PM
      Auto it will be then, now to bolt up one of my 4T65E HD trannies to an engine and get wiring. Dan

chrisgtp (chrisgtp@gmail.com) MSG #6, 11-17-2007 07:31 PM
      I will offer to take the harness and pay cliff I was going to buy one from you any way but i dont need the extra emission stuff but it will not kill me if its there

FIEROFLYER MSG #7, 11-18-2007 09:14 PM
      A little more progress I have inspected and repaired any bad spots on the wiring and started to reassemble the harness on the engine.
This is the wires for the trunk side which includes the EGR, O2 number 1, MAP sensor and injectors 6,4and 2.




Now the firewall side which is the ignition module connector, the boost bypass solenoid and injectors 5,3 and 1.




Now for the trunk side again with the wires all taped up and the wires from the speed sensor, oil pressure sensor and the knock sensor added on from below as well as the alternator wiring made long enough to reach either the stock location or down lower on this side.



Now for the tranny wiring which includes the main tranny electrical connector as well as the neutral start switch, reverse lights and gear selection switch.



Now time to start combining the different portions of the harness together along with the wiring from the starter, oil level sensor, knock sensor and the A/C compressor clutch. I run the wires from the trunk side under the supercharger to clean things up a bit. Also joined in is the wiring from the throttle body which is the MAF, IAC, TPS and IAT. I find this is a good location for joining all the portions together to feed off to the PCM which on this harness will be mounted in the stock Fiero location.




2002z28ssconv MSG #8, 11-18-2007 11:03 PM
      If only you could have more than one "+"...

goatnipples2002 (goatnipples2002@gmail.com) MSG #9, 11-19-2007 12:27 AM
      Thanks alot.

RideZiLightning MSG #10, 11-19-2007 05:00 AM
      WHOA!

Does everyone else do theirs like this? I have always just taken the loom off a couple sections, lengthened and moved some stuff around and re-wrapped it.


darkhorizon MSG #11, 11-19-2007 09:08 AM
      I dont understand it either Z, everyone loves doing the 400% extra work to make sure its done the absolute most complicated way possible.

topcat (tconey01@att.net) MSG #12, 11-19-2007 09:23 AM
     
 
quote
Originally posted by RideZiLightning:

WHOA!

Does everyone else do theirs like this? I have always just taken the loom off a couple sections, lengthened and moved some stuff around and re-wrapped it.


I've rebuilt a harness that was made that way, and it was HORRIBLE. It did work, but there were so many wires that were not needed in the harness that I lost count. The other thing I found was that the person that made the harness lengthened wires that did not need to be made longer, if they had taken the time to unwrap the loom, they would have had enough wire to go to where it was needed. Lastly, by taking the entire harness apart, it will look MUCH neater when you put it all back together.



RideZiLightning MSG #13, 11-19-2007 10:23 AM
      Depends on what harness you use. I have always used the ones from Rivieras, the wiring to the engine is a complete and extremely obvious separate section of the harness. The rest is just excess you can pull right from the two plugs to the pcm.

RideZiLightning MSG #14, 11-19-2007 10:41 AM
      All this terminal has is the injector and sensor wires and that is it, plug it into the other side and just wrap the hunk of wire that leads to the pcm. Everything else can be pulled from the harness



And the new project that it's getting installed on:



I like this one a lot


FIEROFLYER MSG #15, 11-19-2007 11:59 AM
      I prefer my way for a few reasons, 1 it makes for a much cleaner instal, 2 you can make the harness pretty much any way the customer wants for things like alt, ignition module or PCM mounting location. and 3 because I meter every wire as I assemble the harness it limits or even removes the chances of missing broken wires or putting pins in the wrong spot.
This way does require more work and more time but is worth it in the end or atleast is in my opinion.
Now if you would like to take over this build thread go ahead I can always put my time to better use. Dan


joebaldie MSG #16, 11-19-2007 02:03 PM
      FIEROFLYER did my harness and everything plugged right in just like he said all though car didn't start right up.it was not his fault i had a bad icm

TXGOOD MSG #17, 11-19-2007 02:17 PM
      FieroFlyer
I for one appreciate you putting this info on here.
I agree with you. If you are going to go to the trouble of doing a swap why not check everything out including the wiring harness.
Why depend on wiring that may have been smashed or put under stress when someone pulled the engine.
But then again I disagree with someone else on here about putting in a 3800SC without going through the simple act of replacing the main and rod bearings that might have been subject to neglect in the oil change department.


fieroboy_IL (simplydelious2003@yahoo.com) MSG #18, 11-19-2007 02:43 PM
      radioflyer, I have a 4-speed man.(85 GT) on my 3.8L build, and need a harness for it. make it for that and I'll buy it.

darkhorizon MSG #19, 11-19-2007 02:59 PM
     
 
quote
Originally posted by RideZiLightning:

Depends on what harness you use. I have always used the ones from Rivieras, the wiring to the engine is a complete and extremely obvious separate section of the harness. The rest is just excess you can pull right from the two plugs to the pcm.


Its the same on every wbody/hbody harness I have used for swaps. Very easy to cut and pull the body connector wires, basically just stuff going from the fuse box to the body connectors that you take out, very obvious..... Yes you have to take the tape and sheeting off, but still I didnt hardly ever cut a wire while getting everything mounted on the motor.

The advantages that dan outlines are very clear, and I fully agree, I just dont usually care about making everything EXTREMELY clean, I have sheeting over all my wires, and noone complains that it looks out of place. Also its fairly easy to re-combobulated the wiring still without cutting it. Although..

 
quote

3 because I meter every wire as I assemble the harness it limits or even removes the chances of missing broken wires or putting pins in the wrong spot.


I have never worked with a harness that had problems in this area, so I would have t disagree, and honestly I think that it only increases error for the "first timer" that doesnt have a full grasp on whats going on.

There is NOTHING WRONG and in most cases it is much "better" to do it this way if you are looking for a specific look or something, but Z and I are only saying this because a newbie (like I was 2 years ago) might read this thread and decide that it is too hard to do the harness, or that it is too much work, for him not to attempt it himself.



FIEROFLYER MSG #20, 11-19-2007 03:39 PM
      I at no time said or even suggested in any way that this is the only way to do a swap harness. I did state that this is how I do a swap harness and with many years of experience in wiring aircraft for both the Canadian Air Force and civilian aviation as a liscenced avionics tech I like to think I know atleast a little about wiring.
With that all I have to say to the ones who can not help themselves when it comes to budding into things they know little or nothing about is go crawl back under a rock and keep telling your self your work is not the **** that it really is and leave people alone who are trying to help others by sharing their knowledge and time.

For reasons of comfort and warmth I have brought the harness into the house and installed it onto my jig to finish. I have taped up the harness to the point where it feeds off the engine.




On my jig I mount one PCM connector at a time and do one section of each connector at a time one wire at a time. Lenghtening or shortening as needed to keep the harness nice and cleanely run. In this case C2 clear connector is first as it is closest to the firewall when installed in the car.








RideZiLightning MSG #21, 11-19-2007 07:12 PM
      I was in no way saying that the way you do it is wrong or a waste of time

No doubt that your way does produce a better looking, more reliable harness. I'm sorry if that came off wrong


thismanyfieros (toickle74@hotmail.com) MSG #22, 11-19-2007 07:33 PM
      aaahhh dan you are the wiring guru....as far as the other two twits go pound sand.....tim

darkhorizon MSG #23, 11-19-2007 09:33 PM
     
 
quote
Originally posted by FIEROFLYER:

First of all you really need to get a life, secondly I have no desire nor do I feel there is a need to prove any thing to you.
Nor do I feel that doing harnesses is worth the crap of dealing with people like you. You act like some high school punk trying to prove some thing, or you are some dumb high school punk with out enough brains to shut your own mouth.
This is it for me, I will now ignore this post as well as any others your big mouth gets involved with. Dan


 
quote
Originally posted by FIEROFLYER:

darkhorizon I have sat quiet for too long, for the longest time you were kissing up to me e-mailing me quite often asking for info and trying to get me to send my over flow to you. I had no problem with this although I did not appreciate seeing you trying to come off as some kind of 3800 Guru using other peoples info, because you are far from it. Your work from what I have seen is butcher work at best you take every short cut possible and brag about how fast you get things done. You are basically a parott that just repeats what ever you hear with no concern what so ever if the info is correct or not.
At this point I would reccomend you shut your mouth and stop your fingers from typing any more crap before you make any more of a fool of your self. Dan


Isnt dan just the nicest guy out there?



thismanyfieros (toickle74@hotmail.com) MSG #24, 11-19-2007 11:24 PM
      i have met dan in person..i like dan...he is the kind of guy who calls it like he see's it...not enough people like dan in this world if you ask me...i have called dan at all hours of the day with questions and he has always helped me out....i had my car done by dan (as have many others) does he do up threads and brag about it...err no...has he been doing this longer then most..errr yes...while you tend to post and post and post and the more i read your posts i kinda hafta agree with everything dan has said about you darkhorizon...plus just seeing how you and ridezlightening have expressed your opinions and thoughts about why dan does what he does it just confirms your place as a know it all twit....
myself i would want the guy doing my swap to go the extra mile and make DAMN SURE that all the wires in the harness are 100%...that my friend is called good service....if it takes longer so what....we get paid to do the job right the first time...other wise we wouldnt keep our jobs very long now would we???
hope you keep up the good work dan....tim


RideZiLightning MSG #25, 11-19-2007 11:42 PM
     
 
quote
Originally posted by thismanyfieros:

i have met dan in person..i like dan...he is the kind of guy who calls it like he see's it...not enough people like dan in this world if you ask me...i have called dan at all hours of the day with questions and he has always helped me out....i had my car done by dan (as have many others) does he do up threads and brag about it...err no...has he been doing this longer then most..errr yes...while you tend to post and post and post and the more i read your posts i kinda hafta agree with everything dan has said about you darkhorizon...plus just seeing how you and ridezlightening have expressed your opinions and thoughts about why dan does what he does it just confirms your place as a know it all twit....
myself i would want the guy doing my swap to go the extra mile and make DAMN SURE that all the wires in the harness are 100%...that my friend is called good service....if it takes longer so what....we get paid to do the job right the first time...other wise we wouldnt keep our jobs very long now would we???
hope you keep up the good work dan....tim


WHOA! Hey, why don't you go look at my last post? I said absolutely nothing bad about his work or how he does it, and then I even apologized and explained for the misunderstanding


Billybo455 (billybo455@aol.com) MSG #26, 11-19-2007 11:44 PM
      seems like there's a lot of pissed off people on the forum anymore....

RideZiLightning MSG #27, 11-19-2007 11:47 PM
      Seriously man, go back and read my posts. There was not a single thing I said in any of my posts that could be interpreted as rude or that my way is better. I asked is this how everyone else does theirs, and then proceeded to show how I do mine. I even said his way was BETTER! Dan has gotten a lot of flak from some people and I understand how he could have taken it the wrong way though. I don't know enough to make any kind of negative statement about him or his work

RideZiLightning MSG #28, 11-19-2007 11:54 PM
      Dan,

I'm sorry to have possibly contributed to the polluting of your thread.


FIEROFLYER MSG #29, 11-20-2007 10:12 AM
      No Z it is not you its the other guy the crap shooter.
This photo just shows PCM C1 is also complete the same way C2 was done one wire at a time. Also shows that I have started grouping the wires to feed off to the C500 connector, the C203 and the relays that will run the fuel pump and A/C clutch. Also the grounds will be grouped together and lengthened to reach the one stud on the lower bell housing bolt near the starter.
The jig I use has metal plates that stick out so I know where the fire wall will be and where the PCM connectors will be for mounting in the stock Fiero location. For swaps where the PCM will be mounted else where just run all the wires to reach where you wish to mount the PCM and assemble the connector there. Before I made this jig I built all my harnesses on the engine and used a good tape measure to figure out where every thing will need to be located and wired to match. Dan



FIEROFLYER MSG #30, 11-21-2007 10:53 AM
      For wiring the C203 the wires only need to feed a short distance past the PCM connectors for my harnesses I allow 20 inches from the firewall to the C203.
C203 pin A is no longer used as the 3800PCM does not have a shift light option
C203 pin B this is power from the furl pump fuse to the fuel pump relay and also a good spot to tap off +12 v battery power for the OBD II DLC connector. I also use heavier gauge wire salvaged from the Fiero engine harness for fuel pump wiring.
C203 pin C check engine light (MIL) this is from PCM C2 pin 5
C203 pin D this is +12v through the A/C pressure sensors in the front of the Fiero, I use this wire to feed the A/C compressor clutch relay to engage the relay.
C203 pin E oil pressure gauge feed from the oil pressure sensor. For this you need to convert over to a 3 pin oil pressure sensor which is for a gauge not an idiot light. The ones from the 88 V6 Fiero work well here.
C203 pin F this is 12v ignition from the ECM fuse for PCM C1 pin 19
C203 pin G this is the speed sensor high feed to the speedometer. This must be connected to the PCM C1 pin 55 through a buffer circuit on auto swaps
C203 pin H this is no longer used

C203 pin J this is 12v ignition from TBI inj 1 fuse this is where the pink wires from all six injectors is connected then the fuse replaced with a 15 amp fuse.
C203 pin K this is where all the other ignition feeds from the engine are to be connected and the fuse also replaced with a 15 amp fuse
C203 pin L this is power from the fuel pump relay to the fuel pump and also is a larger gauge wire than the one used in the 3800SC cars
C203 pin M this is ground which is connected to chassis ground MAKE SURE PIN M IS NOT CONFUSED WITH PIN N WHICH IS 12V
C203 pin N this is 12v feed for the A/C clutch relay which is switched through the relay to the clutch solenoid green wire
C203 pin P this is the TCC feed from the brake pedal and goes to PCM C1 pin 30
C203 pin R is speed sensor low which with auto swaps goes to ground, on manual swaps gets connected to the purple wire on the speed sensor.


3.8 SC MSG #31, 11-21-2007 01:09 PM
      I have not met Dan in person, but what I have seen here on PFF and his photos that he list in his signature, is great for a person that is a DIY, like me. I have saved a lot of money and have been able to use that money on other parts of the swap, because of him. Dan, I thank you. I have been watching this thread and the harness that you are making. This is pretty much the same way I do my harnesses. Only now, I am making a harness for me and I am going the extra mile to make sure, to hide the wires, plumbing, or cables from showing, when you open the hood. I like that jig that you have there. That is alot more compact than "the engine on a cradle with a false firewall design" that I use. As for the trolls- GO AWAY AND LEAVE US ALONE!!!

Again Thanks,
Don Z.


FIEROFLYER MSG #32, 11-22-2007 10:45 AM
      This the completed C203 with three wires hanging out of the harness the green one is from the PCM C1 pin 55 which is VSS out, the second is pink which is tapped off C203 pin F the ECM ignition and the third is yellow which is from C203 pin G VSS high to speedo. These wires are for the speedo buffer circuit which consists of two resistors, one capacitor and a diode to adapt the PCM VSS out to work on the Fiero speedo.



The C500 takes a little more wire to be able to reach it connection point over above the battery, I have found a measurement of 50 inches from the harness where it goes through the firewall.
C500 pin A2 is ground connect to chassis ground
C500 pin A4 is for starter ignition on auto tranny cars this wire goes to the neutral switch on the tranny
C500 pin B3 is from the charge indicator on the gauge pod it can either be connected directly to the alternator pin L or to the PCM C1 pin 36 then PCM C2 pin 61 connects to the alt pin L. Going through the PCM just gives the PCM control of the alt charging.
C500 pin C1 is the +12v feed to the reverse light switch mounted on the tranny on auto and 5 speed cars it is connected to the tranny switch pin B on the 4T60E and 4T65E trannies.
C500 pin C2 this is the feed from the coolant sensor to the coolant gauge
C500 pin C3 this is the tach feed and comes from the ignition module harness connector pin E which will have to be added into the harness on most cars.
C500 pin D1 is the ground to turn on the cooling fan and comes from PCM C1 pin 6
C500 pin D2 is the ground for two stage cooling fans and comes from PCM C1 pin 5. from my experience only 84 Fiero's with A/C have two stage cooling fans.
C500 pin D3 this is the feed from PCM C1 pin 75 to turn on the coolant lamp on the Fiero gaugse
C500 pin E1 is the return path from the reverse light switch which is connected to the tranny switch pin F on the 4T60e and 4T65E trannies
C500 pin E2 is the ignition feed for the starter on manual tranny cars and goes straight to the starter.
C500 pin E3 is the +12v ignition feed for the ignition module




85LAMB (linck777@netzero.com) MSG #33, 11-22-2007 11:24 AM
      Fieroflyer
I just wanted to thank you for a very helpfull tread
Happy Thanks given and + for you


Misery (ramairiv71@yahoo.com) MSG #34, 11-22-2007 06:56 PM
      Dan,

Keep up the great work, I would guess that there is a large but silent majority, such as myself who has been a member for quite a long time and benefited greatly from the information on this board, but for one reason or another choose not to post but rather use this as a resource of information.You and many others who take the time to share your knowledge and experience with us without all of the grandstanding and finger pointing are very under appreciated so PLEASE continue...

"You get what you give and people get what they deserve"


Fierostarvin MSG #35, 11-22-2007 07:03 PM
      What Misery said!!!

Jncomutt (jncomutt@hotmail.com) MSG #36, 11-24-2007 12:56 AM
      Keep it going, this thread is great!

aaronrus (stickpony@gmail.com) MSG #37, 11-24-2007 03:42 AM
     
 
quote
Originally posted by darkhorizon:

I dont understand it either Z, everyone loves doing the 400% extra work to make sure its done the absolute most complicated way possible.


for once i agree with darkhorizon, however, if you are looking for the cleanest install possible, this is definately the way to go.


FIEROFLYER MSG #38, 11-24-2007 10:17 AM
      Ok the harness is fully assembled the last thing I did was wire up the relays. For the relays there is the Fuel pump relay, the fuel pump speed control relay and of course the A/C clutch solenoid relay. For the fuel pump you can wire it up the same way the Fiero did using the oil pressure switch to keep the pump going once the engine is started which will work just fine. I prefer to wire it up using the 3800SC relays that way the PCM controls the fuel pump, either way it is best to have the wiring diagrams right in front of you to make sure it gets done right.
At this point is there any thing I have missed that needs explaining or photos of shown to help explain how I build a swap harness.
As mentioned numerous times above this is not the easiest or fastest way too build a harness there are many ways to do so this is just how I like to build a harness and how I build the ones I sell to those who either do not have the time to make their own or just want to buy one to save the trouble of building one. Dan


smartaxel (jamesdnye@gmail.com) MSG #39, 11-24-2007 10:45 AM
      Dan,

Thanks for the thread.

I lack the time to do the wiring, and when the time comes will prob. be buying a new harness. This thread is most appreciated. It's a nice, professional looking install!


3.8 SC MSG #40, 11-24-2007 11:11 AM
      You showed C203. But, you might want to show what C500 looks like and how to remove it, for the folks that are not wire handy. This way they will know what connectors to send you. Great write-up!

Don Z.

[This message has been edited by 3.8 SC (edited 11-24-2007).]

NeoNot MSG #41, 11-24-2007 02:01 PM
      Dan,

You might want to check out Radio Shack. They carry a little pin pull for molex connectors and various other connectors that allow you to remove the pins from a wiring harness with no effort. The nice thing about using this little tool is saving the tiny latch tabs that break so easy!!!.

If memory serves me right they are roughly $10.

By the way thanks for the write up on the harness. It may come in handy in the near future if I can decide on what motor I am going to use.


FIEROFLYER MSG #42, 11-25-2007 06:28 PM
      I have a small dental pick that works just fine for removing pins.
The C500 is the one over by the battery on 85 and up Fieros and bolted to the fire wall on the 84 models. It has three parts this is the three parts together.




loosen the nut joining the parts together with a 1/4" socket while gently pulling it apart and you get the two portions off the base.




bend back the two clips on the side and pull the portion that feeds off ot the tail lights from the other part.



Then you have just the engine portion of the C500 which is what is needed for making the swap harness. Then once the harness is done and installed onto the engine you just reassemble the C500 and C203 and the wiring portion of the swap is done other then adding in a few good grounds and connecting the battery up to the starter.



FIEROFLYER MSG #43, 11-26-2007 09:35 AM
      If there is any thing else I can post a picture of or questions to answer feel free to ask.
Now that the harness is complete Chris did you still want to buy it or is there some one else that would like to purchase this harness. Chris has first dibs then if he does not want it I will advertize the harness in the mall where payment will go to PFF not me. Dan



Misery (ramairiv71@yahoo.com) MSG #44, 11-26-2007 08:56 PM
     
If Chris doesn't want it...I'm in !!!

Dan you have a PM!!


FIEROFLYER MSG #45, 11-27-2007 08:58 PM
      Seeing as I have not heard back from Chris I guess Misery the harness is yours, make a donation to PFF for $400 US and once I am contacted by PFF to let me know you have made the donation I will ship the harness along with the matching 98 GTP PCM to you. Dan

MstangsBware (stephen_p38@yahoo.com) MSG #46, 11-28-2007 06:02 PM
     
 
quote
Originally posted by FIEROFLYER:

Seeing as I have not heard back from Chris I guess Misery the harness is yours, make a donation to PFF for $400 US and once I am contacted by PFF to let me know you have made the donation I will ship the harness along with the matching 98 GTP PCM to you. Dan


If Misery passes on it then I will take it for a upcoming project. Just let me know.


josef644 (josef644@hotmail.com) MSG #47, 11-28-2007 06:34 PM
      Well done Dan, Very Well Done.
Do you make these for the Cadillac 4.9's swaps also?
Thanks
Joe Crawford
Texas


FIEROFLYER MSG #48, 11-28-2007 06:34 PM
      Turns out Chris does want it so I will now start on another for Misery. Any one need one for an 84 as I have one manual tranny and one auto tranny swap harness, one from an 84 I was going to do a swap on for myself and the other from a person who changed his mind after ordering the harness. Also have one for an 85 up with the auto tranny that I made for a customer where I was confused about what he wanted and ended up building him a manual tranny harness. That is what happens when you do over 40 harnesses in just a few months you get a little confused. Dan



Fierostarvin MSG #49, 11-28-2007 07:22 PM
      Dan, Can you tell me about the 84 auto harness? What's included, how much. thanks Jeff

FIEROFLYER MSG #50, 11-28-2007 10:25 PM
      The 84 auto harness is built for the PCM and ignition module to be mounted in the old battery location, the alternator in the stock location or low on the trunk side and has A/C wired into the harness. The harness has the C203 and C500 already on it so you just would need to install the harness on your engine and connect the C203 and C500 then run a few extra wires to your fuse panel as the 84's do not have enough sources of ignition to work with in the harness already. It is all wired for a 98 GTP PCM which I can supply with the harness, the emissions wiring is in the harness as well but you can just not connect them if yu do not want all the emissions working. I would like $400 for the harness and its matching PCM. Dan

chrisgtp (chrisgtp@gmail.com) MSG #51, 11-29-2007 05:40 AM
      sorry i didnt see that this was ready to go. I was looking for a pm

dsnover MSG #52, 11-29-2007 09:09 AM
      OK, getting geared up to do a swap on my 88 (and probably the 87), to a 96 3.4 DOHC. I realize that the harness will obviously be different, but nonetheless, I _really_ apprecate this thread. One question, though for the master: What method do you use to lengthen a wire? Most of the 'splice' connectors that I've seen aren't something I'd like to depend on, and since you have experience in the aviation industry (where this stuff is critical), what is the BEST method to ensure a long term, durable splice?

Thanks,

Darryl


Fierostarvin MSG #53, 11-29-2007 09:36 AM
      Dan, I would like to buy the 84 auto harness send me instructions Jeff

FIEROFLYER MSG #54, 11-29-2007 10:09 AM
      PM sent. For lengthening wires I have left over wires from harnesses and a few cut up 3100 harnesses I use so I can keep the coulour and wire gauge the same when working on harnesses. For soldering I twist the wires tightly, solder being carefull not to use too much solder then use heat shrink to seal up the connection and for doing large bundles it is a good idea to stagger the connections. Also use proper 63/37 flux core solder that has non acidic flux, take your time running the wires and tape the harness up very well before applying the loom. I go through many rolls of electrical tape on each harness making sure the harness is well sealed and protected.
Unfortunatly on air craft you will quite often find butt splices being used for quick repairs as well as many other things that should not be done. In the Air Force when a harnes is damaged the usual practice is or atleast was to replace the entire harness by making up a new one and properly labeling all the wires in the harness. We had large sheets of plywood with harness routings drawn on them and posts to wrap wires around where each connector would be to make it easier to build new harnesses because you really couldn't build the harness inside the air plane or on the engine like you can with a car engine. Dan


Formula88 MSG #55, 11-29-2007 11:10 AM
      (+) for the great writeup!

You're right, Dan, your method isn't the quickest or easiest, but I think it's the best way to do it. If I were going to buy a harness, yours is what I'd buy - not one that's been hacked and patched.


Fierostarvin MSG #56, 11-29-2007 11:28 AM
      Dan if the PM was to me I don't see it

darkhorizon MSG #57, 11-29-2007 11:54 AM
     
 
quote
Originally posted by Formula88:

(+) for the great writeup!

You're right, Dan, your method isn't the quickest or easiest, but I think it's the best way to do it. If I were going to buy a harness, yours is what I'd buy - not one that's been hacked and patched.


Just so you know, this wiring harness is "hacked then patched", just like anyone else's....


FIEROFLYER MSG #58, 11-29-2007 03:56 PM
      Not sure if I would called it hacked or not seeing as I am not just cutting wires I am stripping the harness down completely then building it back up from scratch. But if it makes your feel better about your self then we can just call it a hack job, there feel better now.
Like I mentioned before I am not saying the way I do things is the right way or the only way, I am just showing how I prefer to do things to give people who want to build their own harness a different way that in the end gives them a nice clean job and to show that any one can do a good job if they just take their time. Dan


Fierostarvin MSG #59, 11-29-2007 05:43 PM
      PM sent

Misery (ramairiv71@yahoo.com) MSG #60, 11-29-2007 08:55 PM
     
 
quote
Originally posted by darkhorizon:


Just so you know, this wiring harness is "hacked then patched", just like anyone else's....



Scott, thanks for hijacking a very professional and informative thread and showing the folks here that you were unable to retain the the manners and respect that I am sure your parents taught you as child..

It is best to keep your mouth shut and let people think you are mentally challenged than to open it and remove all doubt..


darkhorizon MSG #61, 11-30-2007 01:00 AM
     
 
quote
Originally posted by Misery:
Scott, thanks for hijacking a very professional and informative thread and showing the folks here that you were unable to retain the the manners and respect that I am sure your parents taught you as child..

It is best to keep your mouth shut and let people think you are mentally challenged than to open it and remove all doubt..


who are you now? hmm? A "loyde nut swinger"?

I didnt hijack anything, this is a PUBLIC FORUM, if you dont think my post was accurate, you can not read it or rebuttal it.


RideZiLightning MSG #62, 11-30-2007 01:04 AM
     
 
quote
Originally posted by Misery:
Scott, thanks for hijacking a very professional and informative thread and showing the folks here that you were unable to retain the the manners and respect that I am sure your parents taught you as child..

It is best to keep your mouth shut and let people think you are mentally challenged than to open it and remove all doubt..


5 posts and you are already calling people out?

Sheesh


TXGOOD MSG #63, 11-30-2007 08:09 AM
      Once again, the post above shows you have people who would rather do things 1/2 **ssed than doing it right the first time.
I think Fieroflyer is doing the 3800 swap crowd a good service even providing the info for redoing a wiring harness. He makes them and sells them and at a good price, but to show people how he does it when he could just say "pay me and I will do it" I think is helpful.
I have read and seen in the past where some of these swaps create problems for the person doing them and I think some of it come down to trying to do it on a limited budget.
Just as Loyde states on his site, "the wiring harness is one of the make or break" parts of the swap.
If you are going to do a swap why not go through as much as you can including wiring, engine internals, brackets for the alternator, etc.
When it comes down to it, the 3800SC should be just as dependable sitting in a Fiero as it is sitting in a Grand Prix or whatever car ir came from.
I am not good with wiring and I can`t weld, so when it comes time to do my swap I will depend on the people who have a proven product to make my swap as dependable as possible.
Just my .02


RideZiLightning MSG #64, 11-30-2007 11:39 AM
      There wasn't any talk of half-a$$edness, just that it doesn't have to be pretty to work properly.

This is the harness from the 3.8sc car skitime first rode in:



That looks like he did what I did my first time. Leave it how it is and just modify some stuff to get it to work. Nothing pretty or fancy

Now here is skitimes:



See what I'm getting at?

But, I think we all agree that it is worth the extra effort to make it look nice. IF that matters to you, because it doesn't to some. Just look at Scott's whole car and you'll know what I'm talking about lol

Thanks Dan for the write-up


TXGOOD MSG #65, 11-30-2007 11:52 AM
      My post wasn`t really directed at you, and I don`t mean a showcar harness, I just feel that if everything you put into a car is not checked out ie. harnesses, engine internals, bracket integrity etc
that you are asking for trouble and I for one would rather do it once.


darkhorizon MSG #66, 11-30-2007 12:21 PM
      Wiring is not taboo, it is seriously 30 or less connections you have to make, and MORE THAN half of them are just making pink wires go to switched 12 volts. A harness is NOT make or break, its make or your to stupid to connect a few wires using, OMG like tools. Someone trying to SELL harnesses might suggest they are "make or break" but it really isnt, he is just trying to trick people into paying $1000 for a few hours of wrapping electrical tape around some wires after connecting them to very well documented places (3.4dohc and my thread has been around for more than a year, see comment).

Ryan has had full pinout lists on his gmtuners.com site for MANY years now, and has also been an authority on wiring advice for much longer than I have.


darkhorizon MSG #67, 11-30-2007 12:23 PM
     
 
quote
Originally posted by TXGOOD:

My post wasn`t really directed at you, and I don`t mean a showcar harness, I just feel that if everything you put into a car is not checked out ie. harnesses, engine internals, bracket integrity etc
that you are asking for trouble and I for one would rather do it once.


HARNESS INTEGRITY? How is a stock GM harness with NO SPLICES routed in the stock locations going to fail more than a harness that has more splices and routing wires in "experimental" locations? i said before that I have helped more people with failed vendor harnesses than custom made ones, and I know more people with custom "hacked" harnesses.


TXGOOD MSG #68, 11-30-2007 12:34 PM
      I would not pay 1000.00 for a wiring harness but I would pay 400.00 for one.
I don`t know Darkhorizon who has recently pissed in your Cheerios and I thought in the
past that you had a lot of good ideas etc. but recently I have seen a couple of threads where you
posted sarcastically where you don`t see why anyone would do something a certain way when in your opinion it`s not necessary.
I might have a difference of opinion on different things and I might put my two cents in, but I certainly don`t make it sound like if someone else decides to follow the threads advice that he is just wasting his time.


Formula88 MSG #69, 11-30-2007 12:51 PM
      Once again darkhorizon shows that everyone must do things his way or he will whine and complain about how stupid they are.

Dan provides a quality service to the people who want to swap a 3800SC into their car. Others such as Purple Reign offer engine mounts. You don't have to agree with how they do it. If you want to do it yourself, more power to you, but stop acting like your way is the only correct way.

You complain about Archie
You complain about Lloyd
You complain about Dan

Dude - just start your own forum where everything is done your own way and STFU here. I, for one, enjoy these technical posts and appreciate the extra time and effort it takes to post them and don't appreciate people like you sending it to the Trash Can.

If you want to show people how you think it should be done - post your own build threads and dazzle us with your craftsmanship.


oldfiero (twalker34@triad.rr.com) MSG #70, 11-30-2007 12:56 PM
      Dan, can you give us more info on the Speedo buffer and where you placed it in the wireharness? I just starting my swap and found your thread very informative. Tkx Tom



LAMBO (toddlamb@augusthome.com) MSG #71, 11-30-2007 01:11 PM
      Dan, I just thought I'd pop in here and let you know that I'm very pleased with the work you did on my harness. For less than $400, you saved me a lot of time and that's definately worth it to me.

The way I look at it, there's two ways to do the wire harness on the 3800 swaps, 1. for show 2. for the driver. Dan gives you a very well done harness that looks factory stock which was perfect for my situation because I'll drive the car every day. I don't spend endless hours detailing my engine bay for a show car, so hiding the wires doesn't make any diff to me.

Once again, thanks Dan for providing the Fiero community an excellent service.


FIEROFLYER MSG #72, 11-30-2007 02:39 PM
      Would like to thenk the people for their kind words, it is good to see there is a lot more good people on here then bad.
The speedo buffer is easy to make, I instal it in the harness near the C203 when making harnesses for sale and right at the speedo when I am doing the full swap on a car.
I can not take credit for the circuit I got the diagram from Fieroaddiction long ago when he still had the diagram up on his website. Seeing as he no longer has the diagram on his website I don't feel that I have the right to post it, I will contact him for his permission then post it if it is ok with him. Dan


oldfiero (twalker34@triad.rr.com) MSG #73, 11-30-2007 02:56 PM
      Thanks, the more info I get the better my swap will be. I'm sure that it's just an RC intergrator, but better to know what already works verses recreating the wheel.

Tkx,

Tom



darkhorizon MSG #74, 11-30-2007 04:50 PM
      please quote me where I said dans harness were bad.

3.8 SC MSG #75, 11-30-2007 05:56 PM
     
 
quote
Originally posted by darkhorizon:


Just so you know, this wiring harness is "hacked then patched", just like anyone else's....


There you go!

And just to let you know, GM factory harnesses have spices in them too.

[This message has been edited by 3.8 SC (edited 11-30-2007).]

darkhorizon MSG #76, 11-30-2007 06:10 PM
      sorry, thats just wrong, try again.

3.8 SC MSG #77, 11-30-2007 06:24 PM
      Nope, I don't think so! This is how everyone else sees it.

[This message has been edited by 3.8 SC (edited 11-30-2007).]

darkhorizon MSG #78, 11-30-2007 07:32 PM
      LOL "sees it" eh?

SuperchargedV6 (rborecky@roadrunner.com) MSG #79, 11-30-2007 08:09 PM
      I have watch Darkwhorizan steal allot of threads in this manner and it is wrong. The best way to make it easier to deal with him and ignore him is to think of this picture below everytime he post his nonsense.


RideZiLightning MSG #80, 11-30-2007 08:31 PM
      At least he doesn't post dumb sh*t like that.

You are just as bad, if not worse. Every post I have ever read from you is nothing but bull. At least Scott is giving some advice, however opinionated it might be. He has helped ALOT of people, no matter how he can be sometimes.

That is offensive to more than just him dumba$$. There is nothing funny about mental disabilities or people pretending to be disabled dude

GROW UP

[This message has been edited by RideZiLightning (edited 11-30-2007).]

smartaxel (jamesdnye@gmail.com) MSG #81, 11-30-2007 08:52 PM
      So, how can we keep this from the trash can? It's a legit posting, with good information.. Let's not let it get ruined with bickering.

1. It serves to show those of us with more money then time where we can get a quality harness..
2. it shows those of us with more time then money how to make our own- if we choose to use Dan's routing.
3. it also shows other options- including cutting an OEM harness.

Can we agree to disagree? There are many ways to go about things..This is just one. If anyone disagrees, by all means create another post, with your pics, and explain how you do things.. This gives everyone options- but keeps each thread tightly composed, and viewable.

Personally I have a car with the "Pre-Skitime" wiring.. I have had quite a few problems so far-wires pulling apart, wires getting cut while driving etc. In my case, I work a lot, and have zero freetime to build my own harness. I would happily pay for a nice, clean, reliable harness- it just makes more sense for my situation.


josef644 (josef644@hotmail.com) MSG #82, 11-30-2007 08:53 PM
      Dan , and others following this thread, I am watching closely as I plan on doing this to a 4.9 sometime in the next 6 months. Every time you post, I and others, learn something new. Please don't get discouraged and stop your good efforts because of some child like behavior. I thank you for your good efforts.
Joe Crawford, Texas


FIEROFLYER MSG #83, 11-30-2007 09:23 PM
      If you give me the year of the 4.9 you are using I can see about getting you the wiring diagrams for it. Dan

josef644 (josef644@hotmail.com) MSG #84, 11-30-2007 09:35 PM
      Thanks, but I'M not that close yet. I have 9 grandchildren who's Christmas will come first. I can play again right after New Years Day ! But beleive me I am learning things at a fast rate.
Joe

[This message has been edited by josef644 (edited 11-30-2007).]

topcat (tconey01@att.net) MSG #85, 12-01-2007 04:09 AM
     
 
quote
Originally posted by smartaxel:

So, how can we keep this from the trash can? It's a legit posting, with good information.. Let's not let it get ruined with bickering.

1. It serves to show those of us with more money then time where we can get a quality harness..
2. it shows those of us with more time then money how to make our own- if we choose to use Dan's routing.
3. it also shows other options- including cutting an OEM harness.

Can we agree to disagree? There are many ways to go about things..This is just one. If anyone disagrees, by all means create another post, with your pics, and explain how you do things.. This gives everyone options- but keeps each thread tightly composed, and viewable.

Personally I have a car with the "Pre-Skitime" wiring.. I have had quite a few problems so far-wires pulling apart, wires getting cut while driving etc. In my case, I work a lot, and have zero freetime to build my own harness. I would happily pay for a nice, clean, reliable harness- it just makes more sense for my situation.


Great response. I am in the same boat where I do not have the time to make a harness... heck, it took me over three months to complete an intercooler install, and that should be a one weekend/one day project. I will gladly pay what Dan asks for a harness, and I am very comfortable around wiring. The thing I really appreciate about this thread is the step by step picture instuctions. If I were to ever take on another conversion, I will absolutely buy a harness from him.


Khaos88GT (iluvcandy76@hughes.net) MSG #86, 12-01-2007 05:30 PM
      O.K. maybe I missed it. I understand the c500 connector is a junction block that is part of the Fiero, but the c203 connector is that part of the original Fiero wiring too or something that is gonna come off the 3800 wiring harness? Also I noticed that you are labeling the pins A, B, C, etc per connector and stating there old and new location. Are the labeled on the connectors already or something or does everyone else have the GM wiring diagrams in front of them except me? Yeah, I know, dumb questions but I wanna have a nice solid understanding of what I doing before I start.

FIEROFLYER MSG #87, 12-01-2007 08:26 PM
      The C500 is a junction block where wires are fed to the engine and tail lights from the rest of the car. The C203 is a connector inside the console by the computer. It is where some of the wiring from the engine feeds to the rest of the car just like the C500. The letters and numbers are on the connectors if you clean the dirt and crap off them. The C203 has two halves to the connector one has A through H and the other J through R. The C500 has the letters going across one way and the numbers down that is how you get pins like A2 of E3.
So when you make your harness remove the appropriate connector and cut it away from the Fiero engine harness leaving enough wire to work with basically the more wire the better. When your harness is finished you just install it on the engine and plug the two connectors back in.
Because the 3800SC engine harness has the PCM connector on it so all that is needed is to feed the harness with the proper powers and grounds then from the harness feed the proper gauges and the harness is complete.
The main connectors from the 3800SC harness that fed the rest of that car are removed from the harness and rerouted to reach the appropriate connector on the Fiero harness.
For example the C203 connector pin C which is brown with a white stripe is the input to the gauges to work the check engine light that comes from the Fiero ECM. On the 3800SC swap harness you take the wire from the PCM for the check engine light or SES or MIL which ever the diagram calls it and reroute it to the C203 pin C and solder it to the wire you cut from that pin. Dan


oldfiero (twalker34@triad.rr.com) MSG #88, 12-01-2007 08:42 PM
      Dan, by chance did you have the oportunity to get the speedo ckt info?

Tks


Khaos88GT (iluvcandy76@hughes.net) MSG #89, 12-04-2007 04:56 AM
      Thanks for the help. So pretty much if I'm gonna be deleting stuff like boost bypass sylenoid, and egr then just dont include those connections in my harness, pop on block-off plates, and get Lloyde to program my pcm?

Matthew_Fiero (matthewfiero@hotmail.com) MSG #90, 05-21-2008 11:04 AM
      "C203 pin G this is the speed sensor high feed to the speedometer. This must be connected to the PCM C1 pin 55 through a buffer circuit on auto swaps"

and on manuals?


Matthew_Fiero (matthewfiero@hotmail.com) MSG #91, 05-21-2008 11:26 AM
     
 
quote
Originally posted by FIEROFLYER:

C203 pin B this is power from the furl pump fuse to the fuel pump relay and also a good spot to tap off +12 v battery power for the OBD II DLC connector. I also use heavier gauge wire salvaged from the Fiero engine harness for fuel pump wiring.

C203 pin L this is power from the fuel pump relay to the fuel pump and also is a larger gauge wire than the one used in the 3800SC cars



I am a little confused on these two..



FIEROFLYER MSG #92, 05-21-2008 07:37 PM
      The fuel pump wiring for the 97 to 2000 models uses two relays one is the fuel pump relay and the other the fuel pump speed control relay. Basically the fuel pump relay switches the +12 volts coming from C203 pin B to the fuel pump through C203 pin L.
The speed control relay switches in and out the fuel pump dropping resistor so the +12 volts either goes through the resistor or bypasses the resistor giving the pump full power.
If you do not want to use the resistor just do not wire it in, what I do then is run the wiring as if the resistor is used then short the wires together that would have fed the resistor giving the pump full power all the time.
the only draw back is the pump is a little noisier during light driving where the SC is not producing boost. Dan


Matthew_Fiero (matthewfiero@hotmail.com) MSG #93, 05-21-2008 07:52 PM
      Ok thanks, I understand now. It IS like I imagined, but it didn't make sense that it would go to an outside relay just to come back to the C203 again..

just off hand, do you have any of those resistors?


darkhorizon MSG #94, 05-21-2008 08:36 PM
      I have a bunch of them... but you most likely dont want to mess with it..

You need to put a whole load of relays in to get the resistor working correctly, its sorta a pain.


FIEROFLYER MSG #95, 05-22-2008 08:14 AM
      The resistors are known to fail leaving you stranded unless you short out the connector to bypass the resistor but if you want to use one I have a few spares hanging over my work bench from GTP's and Regal GS's I have stripped. Dan

Matthew_Fiero (matthewfiero@hotmail.com) MSG #96, 05-22-2008 10:46 AM
      I wont use one

Matthew_Fiero (matthewfiero@hotmail.com) MSG #97, 05-22-2008 03:01 PM
      Do I still use the grn/blk wire to go to the pcm pin clear pin 3?

FIEROFLYER MSG #98, 05-22-2008 09:47 PM
      You mean the dark green with white wire for the fuel pump relay yes that is the +12 volts to turn on the fuel pump relay. Dan

1988Formula MSG #99, 05-23-2008 12:01 AM
      On an 1997 GTP OBD II PCM would the first configuration i have drawn be the correct one that you are talking about above?
I had originally thought that i only needed to run the wiring as drawn in the bottom configuration (in which case I would simply unplug the wire to pin 27 on PCM connector C1)
Both configurations run to socket A on the fuel pump relay.



Dan


FIEROFLYER MSG #100, 05-23-2008 08:46 AM
      The second one where the fuel pump relay is controlled by the one dk grn/white wire from the PCM. The second wire from the PCM for the speed cntrol controls another relay if you decide to use it.
Basically if you are not using the dropping resistor the fuel pump is wired the same as the non super charged pumps. Dan


stinky817 (b.stinski@gmail.com) MSG #101, 11-26-2008 11:55 PM
      here's a bit of an odd question here. what about using a scan tool for diagnosis/monitoring... would you still use the ALDL connector? or would you have to add in an OBD II connector somewhere. I see that you're using OBD II ECU's, and i'm just curious how all that works. i'm thinking of eventually moving to an obd ii motor, but still gathering information to see if it's all possible

FIEROFLYER MSG #102, 11-27-2008 09:46 AM
      Just get get an OBD II data link connector from a Grand prix or other 3800 series II car and wire it into the harness, I wire them in to be mounted in the stock location but they can be wired in to be mounted any where. I say get them from GP's or other 3800 cars because some of the other cars like the Sunfires have a different connector it still has the same electrical connection but does not have the holes for mounting the connector like the GP ones have.
For wiring the connector needs +12 volts battery, two wires to ground and the connection to the PCM (purple wire in most cases). Any other wires on this connector are not used in the Fiero swap they are for things like the radio or the heater system. Dan


86GTSCRocket (ccline746pk@netzero.com) MSG #103, 12-13-2008 10:52 PM
      FieroFlyer, Im in the process of putting a 2001 3.8 SC GTP with the auto trans in my 86 GT 2.8 auto, and would like to know how much you currently charge for a harness and what is your turn around time?

Thanks, Chris


FIEROFLYER MSG #104, 12-14-2008 10:37 AM
      I charge $500 per swap harness when supplied with a 3800 harness to work with and $550 if I have to go buy one to work with, turn around time depends on how many I have to do at the time.
I do not take in more then three harnesses at a time to keep from falling behind so turn around time is from one to three weeks. Dan


86GTSCRocket (ccline746pk@netzero.com) MSG #105, 12-15-2008 04:20 PM
      I would like to send my harnesses as soon as possible, as I could do it but would rather let someone who has done this before and already knows what they are doing, as is obvious in this thread! Please send me a PM asap. I am sure things will be slower as its the holidays, but I will be working on it steadily and hope to have it on the road in a couple months.

Thanks,
Chris


FIEROFLYER MSG #106, 12-15-2008 05:23 PM
      PM sent. Dan

iluvsd619 (luv6192000@yahoo.com) MSG #107, 12-15-2008 11:40 PM
      Hey FieroFlyer. Not sure if you recieved my pm's. Im very intersted in a 3800sc harness as well.

PM sent


BMTFIERO (bmtfiero@outlook.com) MSG #108, 12-16-2008 12:18 AM
      DAN
PM sent


Khaos88GT (iluvcandy76@hughes.net) MSG #109, 12-27-2008 04:51 PM
      Dan where do the 3 wires off the 88 Fiero oil pressure sensor go to in regards to the 3800 harness?

FIEROFLYER MSG #110, 12-27-2008 05:07 PM
      With the oil pressure sensor if the 98 GTP PCM is used you send two wires to the PCM and the third is for the Fiero gauge just follow the diagrams.
For 99 and up series II the PCM no longer gets oil pressure info so only the one wire goes to the gauge unless you want to wire the oil pressure sensor into the fuel pump wiring like the Fiero did. Dan


Khaos88GT (iluvcandy76@hughes.net) MSG #111, 12-28-2008 02:52 AM
      Will the fuel pump operate as it should if you don't wire it into the oil pressure switch?

Dennis LaGrua (dlagrua@comcast.net) MSG #112, 12-28-2008 10:15 AM
     
 
quote
Originally posted by Khaos88GT:

Will the fuel pump operate as it should if you don't wire it into the oil pressure switch?



Yes, provided the relay is wired in correctly. The wiring scheme used on my 3800SC does not have the extra fuel pump circuit path provided by the oil pressure sensor and it runs fine. The parallel circuit connection to the fuel pump at the oil pressure sensor was originally put there to provide a power back up if the fuel pump relay burned out or it might have been an extra current path to ease the load on the relay contacts. Without it you don't have backup protection but I get around this by carrying an extra relay that I can just plug in if it goes out. Since I use the GTP fuel pump relay and it just plugs into the extra fuze box that is in my wiring changing it is a 2 minute job,



FIEROFLYER MSG #113, 12-28-2008 11:04 AM
      And here I thought the fuel pump wiring on the Fieros went through the iol pressure sensor so the fuel pump would be shut off if the oil pressure drops too low.
For the 3800 SC just run the oil pressure sensor to the gauge through C203 pin E and wire the fuel pump relay as the diagrams show, there is no need to include the fuel pump dropping resistor with its extra relay into your harness as it is not of much use and is prone to failing. Dan


Khaos88GT (iluvcandy76@hughes.net) MSG #114, 12-28-2008 12:50 PM
      10-4.

MAN IF I HAD THE MONEY I WOULD BUILD A "FORUM FIERO" IN HONOR OF ALL THE AWESOME PEOPLE AND HELPFUL MEMBERS IN THE FIERO COMMUNITY!!!!! Something with like a paint job that incorporates a little bit of what everyone here that helps at is good at like.................. Dan would get a mini wiring decal, Dennis you'd get a like an axle decal, Ryan would get a PCM decal, Lloyde an Enron logo(LMAO, wait losing my money sucks, O well I can still laugh about it)....................Well yall get that idea! I think it'd be cool anyway.


Flyboy81 MSG #115, 02-02-2009 11:33 PM
      I just wanna say that Dan has been most patient with me and helping me through my swap harness. He has provided valued info and all the people who asked questions about wiring and putting it together also did me a great service. Most of you had the same questions as I did. I am using Dan's method and pulling every pin out and refabbing the harness to suit my needs. I have never OWNED a Fiero befor now, MUCH LESS, ever swapped engines into one. This is my first time for all of this and I am doing it all with the help of a few close friends and family. Thats about 3 people by the way. When my swap is complete, and the car is on the road, you can expect to see my pics posted on here showing my complete and NEAT harness on here and it will be my first one ever completed. If a first timer such as myself can do it and make it look like a pro did it, anyone should be able to follow Dan's instructions and get it right and make it look good.

Thanks Dan! A+!


Flyboy81 MSG #116, 02-03-2009 07:40 PM
     
 
quote
Originally posted by FIEROFLYER:

With the oil pressure sensor if the 98 GTP PCM is used you send two wires to the PCM and the third is for the Fiero gauge just follow the diagrams.
For 99 and up series II the PCM no longer gets oil pressure info so only the one wire goes to the gauge unless you want to wire the oil pressure sensor into the fuel pump wiring like the Fiero did. Dan


Which pins do the 2 wires go to on the 98 PCM. I have a 97 harness pinned to work with a 98 GTP PCM. I will add them if need be.


darkhorizon MSG #117, 02-03-2009 07:59 PM
     
 
quote
Originally posted by Khaos88GT:

10-4.

MAN IF I HAD THE MONEY I WOULD BUILD A "FORUM FIERO" IN HONOR OF ALL THE AWESOME PEOPLE AND HELPFUL MEMBERS IN THE FIERO COMMUNITY!!!!! Something with like a paint job that incorporates a little bit of what everyone here that helps at is good at like.................. Dan would get a mini wiring decal, Dennis you'd get a like an axle decal, Ryan would get a PCM decal, Lloyde an Enron logo(LMAO, wait losing my money sucks, O well I can still laugh about it)....................Well yall get that idea! I think it'd be cool anyway.


and I get a burning brown bag.


FIEROFLYER MSG #118, 02-03-2009 09:22 PM
      For the 98 GTP PCm the tan with black wire from the oil pressure sensor goes to PCM C2 (clear) pin 19 and the black with white goes to chassis ground. With a three pin sensor like the 88 Fiero used the third wire is for the gauge. Dan

Flyboy81 MSG #119, 02-03-2009 09:59 PM
      Cool thanks Dan. Theres a e-mail your way from me. Just kind of a "making sure Im doing it right" kinda thing.

Dennis LaGrua (dlagrua@comcast.net) MSG #120, 02-04-2009 09:33 AM
     
 
quote
Originally posted by FIEROFLYER:

Not sure if I would called it hacked or not seeing as I am not just cutting wires I am stripping the harness down completely then building it back up from scratch. But if it makes your feel better about your self then we can just call it a hack job, there feel better now.
Like I mentioned before I am not saying the way I do things is the right way or the only way, I am just showing how I prefer to do things to give people who want to build their own harness a different way that in the end gives them a nice clean job and to show that any one can do a good job if they just take their time. Dan


I believe what Dark is getting at is that your harnesses use a number cut wires that are soldered together and shrink wrapped as opposed to running a completely solid wire from connector to connector. I've seen your harness and I will say that you do a nice job and they apparently work. This is not to say that your method isn't good as most Fiero swaps use spliced harnesses. The only company that I know of who builds a completely new swap harness from scratch (without any splices) is Fuel Injection technology but they do cost a bit more that yours do.



FIERO1985 (vwfiero@gmail.com) MSG #121, 02-14-2009 02:52 PM
      PM SENT TO YOU DAN



RumbleB MSG #122, 02-16-2009 06:53 PM
      Dan,

I was wondering, what oil sending sensor, you use? I have heard that the 88 Fiero oil sensor is the correct one to use.
But, I have also been told, that the others sensors are O.K. to use, as well. Are the connectors the same, on all years?


Dennis LaGrua (dlagrua@comcast.net) MSG #123, 02-16-2009 07:23 PM
     
 
quote
Originally posted by RumbleB:

Dan,

I was wondering, what oil sending sensor, you use? I have heard that the 88 Fiero oil sensor is the correct one to use.
But, I have also been told, that the others sensors are O.K. to use, as well. Are the connectors the same, on all years?



If I may give my input. The 88 Fiero sensor gives the best fit and will drive the 85-87 gauges.. However, that style sensor was made in two different resistance ranges ( as it was used on many GM cars) and if its not AC Delco specific to an 88 chances are that the one that you buy locally may or may not work. I purchased one locally and had to add a 300 ohm parallel resistance to calibrate it so it would work correctly. You''ll know if you have the right sensor right away as the wrong one will peg your gauge.



RumbleB MSG #124, 02-16-2009 10:50 PM
     
 
quote
Originally posted by Dennis LaGrua:
If I may give my input. The 88 Fiero sensor gives the best fit and will drive the 85-87 gauges.. However, that style sensor was made in two different resistance ranges ( as it was used on many GM cars) and if its not AC Delco specific to an 88 chances are that the one that you buy locally may or may not work. I purchased one locally and had to add a 300 ohm parallel resistance to calibrate it so it would work correctly. You''ll know if you have the right sensor right away as the wrong one will peg your gauge.


Thanks! I will keep that in mind, when I go get my oil sensor, Tomorrow. Do you know if all year Fieros have the same connectors?


FIEROFLYER MSG #125, 02-17-2009 07:22 AM
      The 88's got a different oil pressure sensor with a different mstyle connector which is the same style as the newer cars.
You will need to replace this connector to use the 88 sensor also because most 3800's only have a two pin sensor and you need the three pin one.
If you can not find a new connector some where the ones from the Astro vans are the same and are easy to come by.
You can wire in and run the older style sensor but the newer ones work and fit better and are less prone to leaking. Dan


Flyboy81 MSG #126, 02-17-2009 08:33 AM
     
 
quote
Originally posted by FIEROFLYER:

For the 98 GTP PCm the tan with black wire from the oil pressure sensor goes to PCM C2 (clear) pin 19 and the black with white goes to chassis ground. With a three pin sensor like the 88 Fiero used the third wire is for the gauge. Dan


On the oil pressure sender connector, there is A,B,C,D. Which ones go where for the computer and chassis ground? Looks to me as if A,C and D are where the wires are on the 88 sender connector. My wire colors are all three the same color, I guess its been replaced with a different connector.


Flyboy81 MSG #127, 02-17-2009 10:40 PM
      anyone?

FIEROFLYER MSG #128, 02-18-2009 09:07 AM
      If you have the three pin connector with the proper colours the black/white is ground the tan/black straight across from it goes to the PCM and the other tan on top goes to the gauge. Main thing is the two straight across from each other is ground and PCM where the one above goes to the gauge.
With the van connector the orange is grounded, the gray to the PCM and again the tan on top goes to the gauge. Dan


85SEJAX MSG #129, 02-18-2009 09:12 AM
      Hey Dan just curious as to the status of my harness and pcm

carbonfiber_kid (keith69@ameritech.net) MSG #130, 03-01-2009 12:45 PM
      Dan
Sent you a PM a while ago about a harness


darkhorizon MSG #131, 03-01-2009 01:38 PM
     
 
quote
Originally posted by carbonfiber_kid:

Dan
Sent you a PM a while ago about a harness


Dan is done with harnesses... But seeing how you are in the area.. I could possibly entertain the idea of coming out and doing the harness with you one night.


Chug MSG #132, 03-05-2009 12:04 PM
      I have a question. I have been looking at just about all the ECM wiring info that is out there. I find some differences in every setup that I see and the setup that I have. I have been studying the pinouts and what to hook up where, I'm finding that on the harniss that I have that some of the wires that call to be hooked up are not in my harness.

The question I have is, if there is a wire that is called for on the C1- C2 connectors and it is not there am I supposed to add the wire or is that something that isn' going to work.

i.e. C500 pin D3 this is the feed from PCM C1 pin 75 to turn on the the coolant lamp on the Fiero Gauge (I don't have a C1-75 wire)


Chug MSG #133, 03-07-2009 08:16 AM
      Anyone??

FIEROFLYER MSG #134, 03-07-2009 06:41 PM
      Unfortunately GM in all their lack of wisdom made wiring differences between the different years of 3800's and models cars for 3800 engines.
What is used on a GTP is not on Bonneville or other car.
You need to make your harness match the PCM you are using for example the coolant light wire is used on the GTP and not Bonneville so if you are using a GTP PCM add the wire if not don't. Dan


Chug MSG #135, 03-08-2009 11:17 AM
      So I'm guessing that I'll need the actual pinout for a 99 Olds LSS before I do anything major to the harniss

can_add MSG #136, 03-12-2009 12:11 PM
      So for the oil pressure Sensor, I have the 2 wire sensor from the 3800sc. One goes to C2 Pin 19, the other is the ground, how or where does the gauge get its reading from?

I want to included the "sport mode" button found in the GTP. It's just one wire that goes to ground right, What Pin does the wire come from?

thanks

Also me and my friends were debating this the other night. Is it better to have two power wires coming from the battery one to the alt and the other to the starter or just to have one that goes to the alt and jumps to the starter. Or does it really matter.


CC Rider (ccriderf1@gmail.com) MSG #137, 03-12-2009 01:01 PM
      one that goes to the Starter and jumps to the Alt.

Dennis LaGrua (dlagrua@comcast.net) MSG #138, 03-12-2009 01:17 PM
     
 
quote
Originally posted by can_add:

So for the oil pressure Sensor, I have the 2 wire sensor from the 3800sc. One goes to C2 Pin 19, the other is the ground, how or where does the gauge get its reading from?

I want to included the "sport mode" button found in the GTP. It's just one wire that goes to ground right, What Pin does the wire come from?

thanks

.


The GTP oil pressure sender won't drive the oil pressure gauge as its a switch not a gauge sensor. You'll need to use the 88 Fiero V6 sender. Also be advised that the temperature gauge will require that you use the early GTP ETS 3 pin sensor. The center pins on thse sensors are the gauge connections. As for the sport mode switch, I don't see this on any of the PCM diagrams that I have.


fierocarparts (doyouneedparts@yahoo.com) MSG #139, 03-12-2009 02:38 PM
      All of this has gone WAY over my head. I know wiring is very simple for me. I guess I will keep this aside until I know the donor car and then it should be clear.
I would like to thank everyone for the input into this very important Fiero piece. Please, in the future be patient as I will be asking these same "stupid" questions. Big thanks to Dan for not being an ass and refusing to help the DIY. I think even with him helping the DIYer he still has more harnesses to build than he has time in which to do them.



darkhorizon MSG #140, 03-13-2009 01:58 AM
      sport mode = performance shift

Its a wire on the pcm that you can send to ground to enable performance shift...... its nothing special if you use a tuned pcm... you pretty much just want the best shift settings at all times.

I use mine for a "severe shift" mode, which puts it into a mode where it wont shift until dang near redline at part throttle.


can_add MSG #141, 03-13-2009 09:53 AM
      ok so I found the performance shift Pin. C2 Pin 21 (for a 98 gtp anyways)


 
quote
Originally posted by Dennis LaGrua:
The GTP oil pressure sender won't drive the oil pressure gauge as its a switch not a gauge sensor. You'll need to use the 88 Fiero V6 sender. Also be advised that the temperature gauge will reqire that you sue the early GTP ETS 3 pin sensor. The center pins on thse sensors are the gauge connections. As for the sport mode switch, I don't see this on any of the PCM diagrams that I have.


Now I'm a little confused for the ECT I have 3 wires.

1 Green - C500 C2
1 Yellow - C2 Pin 26
1 Black - PCM Ground

is this not correct?

The oil pressure I don't know why this is confussing me so much. So I replace the 3800sc oil pressure sensor with a 88 oil pressure sending unit (would my 85 iron duke one work?) Then wire it up Tan/Black to C2 pin 19, Black/White - chassis ground, and third wire to the gauge. Is this correct? Where do I hook into the gauge from, C203 Pin E?

thanks for all the help guys!


Flyboy81 MSG #142, 03-20-2009 12:29 AM
      Im just curious here, but I was told that I could wire pin A on the oil pressure sender, the sender wire, to the gauge and it should read. Is this correct? I guess it would be like running a single wire oil sender? Ive got some SS Competition gauges and it has a sender hookup, + and -, and then the gauge light. I assume that it will run a single wire. Anyway just kinda wanted to see if anyone might be able to enlighten me here.

Dennis LaGrua (dlagrua@comcast.net) MSG #143, 03-20-2009 07:49 AM
     
 
quote
Originally posted by can_add:

ok so I found the performance shift Pin. C2 Pin 21 (for a 98 gtp anyways)
Now I'm a little confused for the ECT I have 3 wires.

1 Green - C500 C2
1 Yellow - C2 Pin 26
1 Black - PCM Ground

is this not correct?

The oil pressure I don't know why this is confussing me so much. So I replace the 3800sc oil pressure sensor with a 88 oil pressure sending unit (would my 85 iron duke one work?) Then wire it up Tan/Black to C2 pin 19, Black/White - chassis ground, and third wire to the gauge. Is this correct? Where do I hook into the gauge from, C203 Pin E?

thanks for all the help guys!


As for the ECT. The center pin #C DK Green Wire is the sensing output to the temp gauge (connect to pin C2 on the C500 connector. If you had a Duke engine this wire should be tan). Pin A Or/Bl wire is the ground (low ref) and B Yellow is the temp sensor signal that goes to the PCM.

As for the oil pressure sensor. My wiring uses the GTP fuze box and fuel pump relay wiring so I only connected pin C ( the center pin) of the oil pressure sender to pin E tan wire on the C203 connector. Again use the 88 oil pressure sender which provides a 90 ohm resistive output at full pressure. There are many aftermarket senders out there that are sold as 88 Fiero oil pressure senders but provide a 120 ohm output that will pin your gauge. Use only the AC Delco senders. I wanted to get finsihed and ran down to Autozone and used an aftermarket sender and had to add a 300 ohm parallel resisitor to prevent the gauge from pegging. They sold me a generic 120 ohm sensor!!! Apparently many GM cars use a sender that looks just like the 88 Fiero unit but put out a different resistance. If you can reuse your old working Fiero sender that will work too but if it is that big can type fittiment issues can result.



bc12dJohn (nitezoo@comcast.net) MSG #144, 03-20-2009 02:19 PM
      I just have to jump in to say 'thank you'. As I followed this thread, it FINALLY sunk in that the one tan wire at C203, E drives both the gage and the warning light. I am using an '88 Fiero oil pressure sender with my 3800. I had made an 'oil light relay' (similar to the one used in some late 80s GMs, like the Park Ave with the digital dash). I was going to use the switch to operate a relay (rather than a back-up for the fuel pump) that would open the light circuit when the switch closed at pressure. Thanks on this one, especially to Dennis and Dan. This discussion has been very informative and enlightening! John

Dennis LaGrua (dlagrua@comcast.net) MSG #145, 03-20-2009 02:27 PM
     
 
quote
Originally posted by bc12dJohn:

I just have to jump in to say 'thank you'. As I followed this thread, it FINALLY sunk in that the one tan wire at C203, E drives both the gage and the warning light. I am using an '88 Fiero oil pressure sender with my 3800. I had made an 'oil light relay' (similar to the one used in some late 80s GMs, like the Park Ave with the digital dash). I was going to use the switch to operate a relay (rather than a back-up for the fuel pump) that would open the light circuit when the switch closed at pressure. Thanks on this one, especially to Dennis and Dan. This discussion has been very informative and enlightening! John

I would not worry too much about the fuel pump (back up) secondary circuit on the oil presure sender. I just carry an extra fuel pump relay in the glove box. In the rare case that the relay goes out, I'll just plug in a new relay and get going again.



FIERO1985 (vwfiero@gmail.com) MSG #146, 03-27-2009 12:55 AM
      did you ever get my pm dan?

can_add MSG #147, 03-27-2009 09:40 AM
     
 
quote
Originally posted by FIEROFLYER:

For the 98 GTP PCm the tan with black wire from the oil pressure sensor goes to PCM C2 (clear) pin 19 and the black with white goes to chassis ground. With a three pin sensor like the 88 Fiero used the third wire is for the gauge. Dan


I'm just wondering about this wire that goes to C2 Pin 19 - In all my pinout diagrams C2 Pin 19 is not used. So what is the point of running this wire?


Emc209i (emc209i@yahoo.com) MSG #148, 03-27-2009 10:17 AM
      Trick question? There is no point, pull it out of the connector.



FIEROFLYER MSG #149, 03-27-2009 07:46 PM
      The 97/98 GTP used it for oil pressure info and the 99 up GTP stopped using it. The Regal as well as many other GM vehicles that have serial data fed gauges continued to send oil pressure info to the PCM but only for feeding the oil pressure gauge.
So the oil pressure info is not needed on the GTP PCM's. Dan


Dennis LaGrua (dlagrua@comcast.net) MSG #150, 03-27-2009 09:58 PM
     
 
quote
ok so I found the performance shift Pin. C2 Pin 21 (for a 98 gtp anyways)


Just for everyones reference; On the 2003 GTP PCM C2 connector, pins 19-21 are not used. Apparently this "performance shift" mode was only used on the earlier 4T65eHD's transmissons. I summize that it was eliminated on the 2003-up trans.



darkhorizon MSG #151, 03-28-2009 02:56 PM
      performance shift was actually removed from most cars in 01, but the functionality stayed in the pcmif you put a pin in the connector and grounded it.

Dennis LaGrua (dlagrua@comcast.net) MSG #152, 03-28-2009 05:55 PM
     
 
quote
Originally posted by darkhorizon:

performance shift was actually removed from most cars in 01, but the functionality stayed in the pcm if you put a pin in the connector and grounded it.


This makes sense but in 2003 when the 4T65eHD was redesigned, I believe that the feature may have been completely removed. Regardless if we want a performance shifts we can do it very easily by adjusting the software. My trans is programmed to shift at 5550 RPM at WOT.



darkhorizon MSG #153, 03-28-2009 07:14 PM
      The perf shift tables are still in the bin file on a 01-03... it has nothing to do with the actual transmission anyway, its just a shift pressure and shift point modifier.

Dennis LaGrua (dlagrua@comcast.net) MSG #154, 03-28-2009 10:34 PM
     
 
quote
Originally posted by darkhorizon:

The perf shift tables are still in the bin file on a 01-03... it has nothing to do with the actual transmission anyway, its just a shift pressure and shift point modifier.


Yes you are certainly correct about this but on my 03 PCM which I believe doesn't have switchable performance shift, the normal and performance shift table settings are identical. I believe this to be GM's answer to saving a 25 cent switch.



War Hammer (oldsouthphoto@yahoo.com) MSG #155, 03-29-2009 02:37 PM
      PM sent



darkhorizon MSG #156, 03-29-2009 07:57 PM
     
 
quote
Originally posted by Dennis LaGrua:


Yes you are certainly correct about this but on my 03 PCM which I believe doesn't have switchable performance shift, the normal and performance shift table settings are identical. I believe this to be GM's answer to saving a 25 cent switch.




That and maybe GM didnt like the idea of it shifting the trans harder.. who knows. some of the base shift logic changed in 01+ years too.


FIERO1985 (vwfiero@gmail.com) MSG #157, 03-30-2009 04:59 AM
      Hey Dan Should I resend that pm to you,


thanks
Dan



ca420 MSG #158, 04-30-2009 01:02 PM
      What AWG wire is used on the PCM? I am running a few new wires and want to get the correct gauge wires.

Fiero Master (kramer@netins.net) MSG #159, 05-07-2009 11:16 PM
      bump for helpful thread!!!!



dobie1 (dobie44@hotmail.com) MSG #160, 06-02-2009 10:55 AM
      I am really sorry to have to do this to anyone but , Caution to anyone thinking of dealling with Dan Mcllmoyle "FIEROFLYER"
I sent him $550 dollars along with my 3800 wiring harness and computer over 4 months ago. He told me it would be a couple weeks to do the new harness up and reprogram the computer.
He has moved will not answer emails and the phone number he gave me is disconneted. This amounts ot fraud over $1000 dollars in Canada


85SEJAX MSG #161, 06-03-2009 11:57 AM
     
 
quote
Originally posted by dobie1:

I am really sorry to have to do this to anyone but , Caution to anyone thinking of dealling with Dan Mcllmoyle "FIEROFLYER"
I sent him $550 dollars along with my 3800 wiring harness and computer over 4 months ago. He told me it would be a couple weeks to do the new harness up and reprogram the computer.
He has moved will not answer emails and the phone number he gave me is disconneted. This amounts ot fraud over $1000 dollars in Canada


Although Dan told you a couple of weeks and you still have not recieved anything I wouldn't get too upset just yet. He told me the same thing back in January. I didn't get it until late april but I did get it. He does not communicate very well or give status updates and I know that he just moved as well. He was extremely backed up with orders due to people just sending him harnesses and money orders without even talking to him first. Try getting ahold of him on (I think this is it) gtfieros.com you might get better results.


Bfisher31286 (bfisher31286@gmail.com) MSG #162, 09-01-2009 10:39 PM
      There are two resistors wired into the stock harness (one a few feet from PCM connection, the other near the ICM). Do either of these have to be kept?

FastFieros (fastfieros@fastfieros.com) MSG #163, 09-01-2009 11:37 PM
      Those are not resistors.. Some of the stock 3800 harness had diodes to prevent noise feedback ( spikes ) to the PCM. They are in the AC comp circuit. You also might be confusing a splice pack with a resistor. There are ground splice packs, pink wire switched 12 volt, and 5 volt reference.

http://www.fastfieros.com still doing wiring too..


Bfisher31286 (bfisher31286@gmail.com) MSG #164, 09-02-2009 08:57 AM
      Ya I think your right about the splice packs. They are both located on ground circuits. I guess I will just chop them out and free up those last few tangled wires.

CC Rider (ccriderf1@gmail.com) MSG #165, 02-22-2013 10:38 AM
      Great Post!

Thanks much!


The_potatoking (the_potatoking@hotmail.com) MSG #166, 05-28-2013 03:59 PM
      Hey fieroflyer. Just checking on my harness. It's been 7 dad since it was supposed to be ready. I've been pming you. Getting a little worried. My number is 9094358206

FIEROFLYER MSG #167, 07-22-2013 09:35 PM
     
 
quote
Originally posted by The_potatoking:

Hey fieroflyer. Just checking on my harness. It's been 7 dad since it was supposed to be ready. I've been pming you. Getting a little worried. My number is 9094358206


Seeing as you have posted in here as well I will reply in here as well your package has now been sent out twice and came back at my expense for both ways both times. It will go back out again this week and hopefully the address you have given me works this time as it is getting quite expensive on shipping with it now being well over $160 so far at my end. Dan


djlamp14 (legolamp@hotmail.com) MSG #168, 01-23-2014 06:47 PM
      What is done with the abs connector wires? There are two red 8 or 10 awg wires and 13 or so small wires in the other part of the connector. I seemed to have missed this in the guide above.
http://s155.photobucket.com...0123_174334.jpg.html


FIEROFLYER MSG #169, 01-23-2014 07:23 PM
      The ABS wiring with its connectors gets removed on the Fiero swap including wires for traction control going to the PCM.
All 3800 EVAP sensors can also be removed as well and just feed the Fiero charcoal canister with a vacuum source off the engine.
Wiring for the oil level sensor can also be removed unless you plan to add in an extra warning light for that.


djlamp14 (legolamp@hotmail.com) MSG #170, 01-23-2014 07:35 PM
      As you can see it has wires going to a body connector. Some of these wires I've traced to cruise control. How will this part of the harness be adapted to the fiero

In this picture you can see the additional connector I'm talking about
http://i155.photobucket.com.../20140123_183300.jpg

[This message has been edited by djlamp14 (edited 01-23-2014).]

FIEROFLYER MSG #171, 01-23-2014 08:58 PM
      That extra connector has wiring for the ABS wheel sensors and such going through it as well as other wiring that is not needed. Nothing to do with the ABS or traction control is used when swapping the 3800 engine into the Fiero. Just remove all wiring for these two systems completely.

FIEROFLYER MSG #172, 01-23-2014 09:00 PM
      For the electronic cruise control control only wire from the PCM you need to use is the VSS out put every thing else gets connected to the column switch through the old Fiero wiring and the wire that the PCM controlled the cruise with gets grounded.

PRFiero (romanp@miamidade.gov) MSG #173, 03-25-2014 06:36 PM
      Dan,

This is Pedro R. I have tried to contact you regarding the hardness I sent you to get either modify for a auto or just simply swapped for an auto. I have sent you a few emails asking you status on it, but I have not heard back from you. More than 15 days have gone by since you told me that it was ready and that you just needed confirmation of my address. Since then I have not heard back from you. I just need to know if it was mailed or not. If you are having any issues with it, let me know, but keep me in the loop.

Thanking you in advance for your prompt response.

Pedro Roman.


FIEROFLYER MSG #174, 04-10-2014 11:04 AM
      The couple year old manual harness you had purchased that I was nice enough to take back and exchange for an auto one at my expense was shipped quite a while ago. So lets see I am out shipping plus the cost of an 04 PCM that was very hard to come by this time of year and my gas and time looking for one and you are,,, you know what forget it not going to go there and no longer going to do this kind of favours any more.

PRFiero (romanp@miamidade.gov) MSG #175, 04-22-2014 04:32 PM
      Dan,
Don't get so upset if I had to post here to get you to answer a simple email, but I had to due something about your careless lack of response. If you had any extra expenses I told you to let me know about them. All I asked from you was to keep me on the loop, to call me or simply send me a message. I strongly recommend that you reconsider the way you communicate with people, specially when we have to put out a great amount of money and trust that one day we receive the service we requested from some unknown, unreachable, and untraceable person behind an email account, and to make it ever worse, from a different country. I FINALLY received the hardness and although I have noticed that it needs a few modifications to say the least, I am thankful for swapping it for me. At least I will not be starting from scratch. I think you said it best when you insinuated saying "let not go there".


FIEROFLYER MSG #176, 04-29-2014 02:27 PM
      See my point is simple this is a topic to help people make their own harnesses not to whine I did this to help not unlike taking an old harness as trade and you were informed that I was having trouble finding an 04 PCM for your harness so any time not spent answering you I was at many different wreckers searching when I could have been doing other things and as for your harness it is built as you requested so your little insult suggests which is kind of funny as it means if the harness is not what you wanted then you gave me the wrong info now time to grow up and let this stay as a topic to help others not whine about your own problems so let it go you got your harness with every thing and it did not cost you so where is the problem. The time I spent searching through snow banks at wreckers could easily been spent on other peoples parts but instead I did yours instead now that was my mistake. So like I said let it go.

djlamp14 (legolamp@hotmail.com) MSG #177, 05-20-2014 10:05 AM
      can someone post a few close ups of the c203 connector. I'm working on an auto 3800sc swap into my manual 2.8 fiero. I found the c500, but unclear what one is the c203.

Do we need to do anything the large connector that goes into the firewall from the fuel pump?


dcarrd MSG #178, 08-10-2014 12:53 AM
      I think I have one of your harnesses Dan(PO installed) but he removed everything to do with the AC(compressor, relay, hoses, condenser, evap, collector). Now Im looking to add the AC back with a 3800 compressor but there are no wires coming from the harness that I can see. Any help would be appreciated.

edfiero (jteague67@outlook.com) MSG #179, 08-27-2014 01:47 PM
      Ok, explain this to a total newb on engine swaps. If I were to take an ENGINE, a WIRING HARNESS and an ECU out of a Bonneville, or Grand Prix, why is all this extra work required?
I'm thinking there a few things that simply wouldn't go anywhere... like ABS.
A couple of new connectionswhich would obviously be different in the Fiero, like hook up to turn the electric radiator fan on.
What am I missing? Why do I need to spend a million hours redoing the harness, or paying someone 500+ bucks to do it for me?
Not trying to be a smart a$$, just don't know, what I don't know.
Thanks



Ken_86gt (ken_86gt@cox.net) MSG #180, 09-10-2014 12:02 AM
      Ed- where do you want to put the PCM? I suppose that you could mount it in the engine bay like the first swaps were done. Then all of the wires for start, run, tach, B+...could be spliced in the engine bay into the original Fiero harness that you cut 12" from the firewall and tape spliced. I think if you are going to take the time to do the harness you will also learn a tremendous amount about how the car works. You still will have to do custom exhaust and engine mounts. If you spent the time to make it look good everywhere else why not make the electrical look good to? Each swap is different and you can make it your own way.

Hawaiian Brian (brian.k.adams@gmail.com) MSG #181, 09-11-2014 12:23 AM
      So Dan, are you still making harnesses ? I'm picking up a running 02 GTP and want to swap it into my 86 5spd Gt.

Thanks

B


mental floss MSG #182, 09-11-2014 03:17 PM
      Thanks for the thread and tutorial.

Eglaore MSG #183, 12-20-2014 11:42 AM
      So maybe I missed it but I'm having a little trouble being sure where the 4 wires from the fuel pump relay go, and the plug from the hd gtp trans with the 2 12guage wires/ not sure where all the wires from this plug go. And one last thing, Fieroflyer you said there is one wire for cruise control that comes from the pcm that just gets grounded, do you know what pin it is? I'm using pcm and wiring harness from 98 gtp and the trans is from 98 gtp to. Thank you.

Oh, does anyone have a link to a diagram for the resistor for the speedo?

[This message has been edited by Eglaore (edited 12-20-2014).]

Eglaore MSG #184, 12-21-2014 11:07 AM
      Ok so I figured out the fuel pump relay. The trans plug I was talking about I think I have most the wirse figured out. the two big wires I was talking about were actually 10guage. The yellow goes to c500 I think and the purple one goes to the starter, It looks like it gets grounded on the starter. Is that correct? There is still 3 wires on that trans plug that I don't have a spot to put: Orange/blk which is pin A, Green which is pin C and Black which is pin D. I'm guessing black gets grounded but not sure. Would appreciate any feedback. Thanks

Spiders1 (spidertink@yahoo.com) MSG #185, 01-25-2015 10:02 AM
      Thank you for sending the pieces I needed to finish up my swap Dan. Greatly appreciated.



FIEROFLYER MSG #186, 02-04-2015 07:35 PM
      Is better to ask me questions by PM as I do not check this as often as I should, on the tranny plug pin B orange goes to the blue wire from C500 for reverse lights and pin F to the green wire from C500 reverse lights and yes black is ground for the selector switch that tells the PCM which gear is selected

Spiders1 (spidertink@yahoo.com) MSG #187, 02-13-2015 12:23 AM
      Flyer did my harness. Fired right up, plug and play. Thanks again.



Adjustso3 (adjustso3@yahoo.com) MSG #188, 02-20-2015 10:54 PM
      I would just like to clear up a few things about Fieroflyer. I have been sending him emails with tons of questions and he might not get back to you right away but does within a couple days. He has been very patient with me in reguards to my newbie questions and always gives me the time of day to answer them. Some of my questions have nothing to do with what he builds. I would recommend everyone to ask him for his email address instead of sending a PM over here. It's not my place to post his email addy so I would just ask him through a PM. Once again Dan, thanks for your time and I'm looking forward to doing business with you.

Lou and Blue (mrlduet@yahoo.com) MSG #189, 03-12-2015 08:42 PM
      I am about to send my harness to Dan. I hear he is the best. He has helped me so much so far via email. Great guy.



Lou6t4gto (loubreslow@gmail.com) MSG #190, 10-23-2019 01:53 PM
      he has helped more people than you even know. be patient, he will get back to you. no need to Flame people