I found a motor from the autowreckers, a 2002 Buick regal I have the computer so I hope thats all i needed. There were a couple wires cut by them. It came with the trans and a casting number 24209508, a quick google told me it was a 4t65e and possibly a hd as it backed a 3800. I've been doing some reading and why do you have to strip the wiring harness just to hook it back up? I will post some pics.
------------------ 86 GT Convertable 3800
[This message has been edited by Tweeder (edited 08-22-2012).]
If you leave the wiring harness as it is mounted on the engine from factory, it will want to plug into your trunk somewhere as that is where it ends on the donor car...the firewall. Stripping the harness allows you to redirect the wires to the fiero firewall opening. Now at this point, some of the wires will be way too long and some may be too short. Don't forget you will have to somehow get the C500 plug beside the battery to mesh with the new engine and harness. It will mate with your alternator, oil pressure, coolant temp, grounds, power supply etc. (if I remember correctly) There are some ways of avoiding connections in the engine bay by splicing into the fiero wiring behind the console that feeds the C500 plug, but that will be up to you...
Make sure to take lots of pics and post em'. It's always fun to watch an engine swap!
Why do you have to build a harness to install a 3800 in a Fiero
1 - In a Fiero the wires need to forwards, not backwards to the dash 2 - In a FWD car the wires generally run to the passengers side to pass through the firewall. In the Fiero some of the wires run to C500 by the battery and some run to the firewall pass through at the drivers right elbow 3 - The PCM in a 98+ swap for a Fiero is normally mounted in the console at the stock location of where the ECM was mounted. The PCM in most FWD 3800s is mounted in the airbox 4 - No 3800s ever used connectors like either C203 or C500 5 - Many FWD harnesses include wiring for the antilock brakes 6 - ALL 3800 SC harnesses are wired for automatic transmissions. None will have the wiring for the Fiero MT VSS or Fiero reverse switch 7 - Many 3800 SC automatic harnesses are NOT wired for the starter wire to run through the transmission PNRD switch - They were controlled by relays that were part of the body harness 8 - Many 3800 harnesses include a VATs module that will not allow the engine to crank without a valid VATs signal 9 - If you take a 3800 FWD harness in full, and try to wire it to pigtails from C203 and C500 you might be able to get the engine to run, that is assuming you disable the starter VATs module however the mess of extra wires that you would have would be horrendous. However if you do please take pictures and post them.
Stripping the harness and then hooking the wires back up to the correct locations is the only way to get a clean and dependable install.
I build swap harnesses, but I have no idea how you can use an existing harness and make it work.
If you leave the wiring harness as it is mounted on the engine from factory, it will want to plug into your trunk somewhere as that is where it ends on the donor car...the firewall. Stripping the harness allows you to redirect the wires to the fiero firewall opening. Now at this point, some of the wires will be way too long and some may be too short. Don't forget you will have to somehow get the C500 plug beside the battery to mesh with the new engine and harness. It will mate with your alternator, oil pressure, coolant temp, grounds, power supply etc. (if I remember correctly) There are some ways of avoiding connections in the engine bay by splicing into the fiero wiring behind the console that feeds the C500 plug, but that will be up to you...
Make sure to take lots of pics and post em'. It's always fun to watch an engine swap!
The 3800 that's in there now has the computer in the trunk. I'll have to take a look at that c500 plug and see how that was done.
I'm a sucker for side projects and DIY so I made my own harness for my 4.9 swap (yet to be proven). If I counted the hours spent researching and building it, I'd have to charge thousands of dollars for it to have been worth my while.
I'll have to give you a call for the next engine swap!
My problem is I'm not sure what is what on the engine to Know what wires are what.
I've never done a 3800 swap, just my 4.9. I'm speaking on that experience alone. Lots of great people here to help you along your way. It sounds like you already have a 3800 in your fiero and you are looking to replace it with another one?
Personally I took my harness apart and labeled each wire, at each end. what it is, where it came from, where it's going. HOURS and HOURS spend doing this but the goal was to learn my harnesses inside and out...mission accomplished. Aside from buying a prefab harness or getting someone else to do the work for free, there are no easy answers that I am aware of. If all you are doing is pulling one engine from your fiero and replacing it with the same engine, I'd just unplug the harness connections at the engine, leave the harness in the car and connect the plugs to the new engine once it's in. If this is the case, just takes lots of pics for your own reference. Perhaps some pics for us to look at will clarify what you have going on.
Best of luck!
[This message has been edited by Reallybig (edited 08-22-2012).]
I've never done a 3800 swap, just my 4.9. I'm speaking on that experience alone. Lots of great people here to help you along your way. It sounds like you already have a 3800 in your fiero and you are looking to replace it with another one?
Personally I took my harness apart and labeled each wire, at each end. what it is, where it came from, where it's going. HOURS and HOURS spend doing this but the goal was to learn my harnesses inside and out...mission accomplished. Aside from buying a prefab harness or getting someone else to do the work for free, there are no easy answers that I am aware of. If all you are doing is pulling one engine from your fiero and replacing it with the same engine, I'd just unplug the harness connections at the engine, leave the harness in the car and connect the plugs to the new engine once it's in. If this is the case, just takes lots of pics for your own reference. Perhaps some pics for us to look at will clarify what you have going on.
Best of luck!
I don't think they're compatible. The one that's in there is a 90 Buick Electra with a th125c and what's going in is a 2002 Buick regal with the 4t65e. But that would be the cats ass if it were so.
Well the huge problem I see with trying to wire up an existing harness is to identify the cut wires as to what they do without having the ability to actually know. I suppose you could test each wire out but that would take a very long time. And by that time, I think you would have been farther ahead to just have taken it apart and done it the easy way - by taking it all apart.
Also btw - usually the temp gauge is not wired in most 3800 SC harnesses. Many times the charge light and temp light is driven not by the PCM but instead by the BCM in the donor car.
Yes the link to gmtuners.com is the right one if you are doing a 98-02 PCM. If you are doing a 97 automatic (4T65E) or a manual transmission, it is my recommendation that you swap to a 98-02 PCM. If you are doing a 96 automatic (4T60E) then you have to use the 96 PCM.
Your PCM WILL need to be programmed to operate correctly with your 3800 swap.
Looking online for a download pdf of a 2002 buick regal so I can figure out whats what on the engine. I seen a few but am unsure what one and I don't want to pay for something I can't use. Any suggestions or links?
Ok take everything back about the harnesses working.
Your 3800 in the car is a Series 1
Your 3800 SC is a Series 2
Totally different computers.
idk what is best. I think the best plan would be to tear apart the 3800 S1 SC harness, and to rebuild it for your application.
Sell the S1 harness with the engine to a Fiero owner and get whatever you can get for it.
Pick up a C500 and C203 connector from the MALL section of the forum.
----------------- The first cut went to the donor fuse box The second cut with the round connector went to the firewall The third cut went to the O2 sensor that was after the CAT converter. You won't be using that with the swap The fourth connector is for the anti-lock brakes on the donor car
[This message has been edited by phonedawgz (edited 08-22-2012).]
Ok take everything back about the harnesses working.
Your 3800 in the car is a Series 1
Your 3800 SC is a Series 2
Totally different computers.
idk what is best. I think the best plan would be to tear apart the 3800 S1 SC harness, and to rebuild it for your application.
Sell the S1 harness with the engine to a Fiero owner and get whatever you can get for it.
Pick up a C500 and C203 connector from the MALL section of the forum.
----------------- The first cut went to the donor fuse box The second cut with the round connector went to the firewall The third cut went to the O2 sensor that was after the CAT converter. You won't be using that with the swap The fourth connector is for the anti-lock brakes on the donor car
For the C500 and C203, I take it I need the ones from a fiero? Whats wrong with using the ones that I have there besides selling the harness as a whole unit? The s1 is knocking but does have ported and polished heads that I was planning on selling eventually.
Yeah you could cannibalize the S1 NA harness to make your S2 SC swap harness. All the computer connectors are different, however many/most of the sensor connectors are the same.
OK, if phonedawgz not going to plug his services I will...
Tweeder, buy a premade harness. Save yourself the headaches, pain, solder burned seat covers etc. Look, after weeks of off and on fiddling with my harness, this is what I still have to clean up once I prove it works;
OK, granted the engine is done with the exception of some loom, a few grounds and the cruise (to be installed later). But much time was dedicated to keeping the wires neat and hidden for a clean engine bay.
Just ask yourself how much time you have, how much money you got, and how much sanity you can sacrifice...
Originally posted by phonedawgz: ----------------- The first cut went to the donor fuse box The second cut with the round connector went to the firewall The third cut went to the O2 sensor that was after the CAT converter. You won't be using that with the swap The fourth connector is for the anti-lock brakes on the donor car
For the first and second, are they needed or is that something that'll get stripped? Also the second one has a small cut arenas ext to the round connector
------------------ 86 GT Convertable 3800
[This message has been edited by Tweeder (edited 08-23-2012).]
For the first and second, are they needed or is that something that'll get stripped? Also the second one has a small cut arenas ext to the round connector
No neither are used when swapping the harness into a Fiero
On a side note, I seen somewhere that somebody hooked a battery to jump the starter so they could do a compresion test on a motor that wad on the bench. I tried that and nothing, I hooked up the + to the larger wire and the - to the smaller wire
Just got the tranny off and the motor's up on the stand. The harness is off and labeled. I have 2 connectors that i'm not sure where they go. the first one is off the same harness and comes after the oil level in the pan. The connector is blue, 2 wires and has the clips on the sides. Then the one that comes in line after that that was up in the pulley system and was ground down by the pulley. Its a long grey connector but can't tell whats on the end of that as its gone? I can put up pics tomorrow, the cameras in the wifes truck at work.
My hat is off to you guys attempting to do the wiring. I'd have better luck trying to learn Latin. Plus, it sucks when you have contrasting color blindness like me! Do you have any idea how bad that sucks when you are in networking? "Hey is this green or orange"? I have learned a trick or two from a friend for that one, I use a light with a green tinted lens to help sort it out. I'd be screwed without it!
Anyway, when I did my L67 swap, I ordered a brand new GM spec harness from Injection Technology. It was kinda expensive, but worth every penny!
[This message has been edited by BV MotorSports (edited 08-26-2012).]
A six day old post and already we've got missing pictures. Photobucket sucks for use in this forum. Use PIP.
[EDIT] I see that the OP has replaced the missing pictures, but I stand by my original comment... The use of Photobucket for posting pictures in the forum sucks. So many useful tech threads are eventually ruined forever when crucial images disappear never to be seen again.
quote
Originally posted by Tweeder:
Odo oops I didn't realize deleting the images from there deleted them from the forums as well. I'll have to repost te images.
[This message has been edited by Patrick (edited 09-04-2012).]
Odo oops I didn't realize deleting the images from there deleted them from the forums as well. I'll have to repost te images. I tried te pip thing and couldn't figure it out so I went the photobucket route.
Got the wiring harness all seperated and coiled. Next will be putting it all back together. I had this connector and wire assortment but am unsure what it is.
In the last picture(not the last on posted but the cluster of pics) with the large D shaped connector at the transmission, what is that for and is it used?, I seem to recall something like that going through my trunk where the computer now is? I also read that I can use the th125c mounting bracket with some gentle persuasion of course. But what about the shifter cables? And what about the shifter in general, I have a 3 speed and am going to a 4 speed. I know I'll have to figure out the cv shafts later after its in depending on where everything sits in the cradle.
------------------ 86 GT Convertable 3800
[This message has been edited by Tweeder (edited 09-04-2012).]
Odo oops I didn't realize deleting the images from there deleted them from the forums as well. I'll have to repost te images. I tried te pip thing and couldn't figure it out so I went the photobucket route.