someone posted that the 4.9 runs rich because of the ps pump?

You need to make sure the PS input to the ECM gets 12V or the ECM will not run in block learn mode and will default to a very rich mixture. Add the 12V and it will not run rich.

which wire?

quote Originally posted by madbrad01: which wire?

C9

Thanks for the info much appreciated.

Mine is running rich which turns on the engine light after the car is warm. My problem is because i'm going straight out of each manifold without a crossover, y-pipe, or cat. conv. To fix this i will eventually buy a heated o2 sensor but that costs $60-100 I believe.

------------------
-Kyle
Email: kakagiraffe@gmail.com
Aim: Littlechugger
1988 Notchback 4.9 V8, 5spd Isuzu, Spec Stage 4
True Dual Exhaust, Delta Cam
1996 Grand Am 3100
2001 Honda CBR 600 F4i

I thought the o2s were heated,both are 3 wire.Besides I have dual 2 inch with cats.

My O2, (only have one) is not heated.

I'm using 92 seville with 2 o2 sensors,heared someone burns a chip for more hp.

quote Originally posted by jscott1: C9

...hey that highlighted diagram looks very familar...

All the 'stock' 4.9s that I have seen do not use the heated sensor, if it has, someone probably added it. Are you able to run a scanner on the engine? Any codes (need a scanner to read the codes, can not be done the old 'Fiero way')?

No i don't have a scanner,and the car is not on the road yet,thanks for the help.i'd thought 3 wire o2s were heated.

quote can not be done the old 'Fiero way')?

Supposed to be able to flash engine codes but I believe they go through the cadillac HVAC controls, which most people do not have ...

quote Originally posted by madbrad01: I'm using 92 seville with 2 o2 sensors,heared someone burns a chip for more hp.

That would be me. email me directly at stickpony@gmail.com , and i will give you detail. my chip will give you a 20HP and 15 ftlbs TQ gain over stock

quote Originally posted by madbrad01: jscott1,are your o2 three wire?

Nope I have the bone stock one wire O2...

And credit for the drawing goes to Tim...I saved everything he has ever posted on the 4.9!

Someone was working on installing the caddy HVAC controls but I believe Katrina ruined their car.

I'm tempted to give it a try...But there is a lot going on between the HVAC and also the fuel display. I'm not sure it's all supported with my chip. It would be worth a try just to find out.

quote Originally posted by Mickey_Moose: All the 'stock' 4.9s that I have seen do not use the heated sensor, if it has, someone probably added it. Are you able to run a scanner on the engine? Any codes (need a scanner to read the codes, can not be done the old 'Fiero way')?

My 95 4.9 has duel 4 wire heated O2's

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quote Originally posted by Rickady88GT: My 95 4.9 has duel 4 wire heated O2's

This may have been on the Sevilles...but my Deville definitely did not have it.

Also, if you want to do the Caddy HVAC, you also need a Caddy BCM, so it gets complicated real fast. I don't know if I'm smart enough to figure it out.

[This message has been edited by jscott1 (edited 12-09-2008).]

quote Originally posted by jscott1: I'm tempted to give it a try...But there is a lot going on between the HVAC and also the fuel display. I'm not sure it's all supported with my chip. It would be worth a try just to find out.

I gave it a shot when I got my install done. Let me tell you there is a ton of stuff going on there. You need the BCM, all 3 displays, heater control box (black box under pas. dash), and the PCM/bcm must be out of the same car. Another issue I ran into is the displays themselves run on a 16V input and for the life of me find out where that power came from. I believe there is a special relay somewhere. Long story short, It would not work for me at all. I still believe its possible and have all the diagrams and info if anyone is interested.

A better plan is to go to E-bay and search "auto X-ray" and pick yourself up a scanner. I got one for $100 shipped and I can now check all my cars, not just the 4.9. It shows most of the info the caddy system has but not everything. The caddy diagnostic system is pretty special for these cars.

I used the caddy dash to display all the diagnostics on my N* car. Basicly I ran a power and a ground wire and the two data link wires into the dash worked like a charm. I did not use it to control the heater or as a dash just as a scan tool.

quote Originally posted by Fiero STS: I used the caddy dash to display all the diagnostics on my N* car. Basicly I ran a power and a ground wire and the two data link wires into the dash worked like a charm. I did not use it to control the heater or as a dash just as a scan tool.

N* is a completely different animal than the 4.9... The 4.9 uses a proprietary OBDI setup that has a lot of funky things going on...it's not just a simple serial data link.

Fieroseverywhere - I would be interested in seeing the diagrams, just to see what's involved.

quote Originally posted by jscott1: This may have been on the Sevilles...but my Deville definitely did not have it.

I believe this is a Deville. My wire diagram says vin B?

quote Originally posted by jscott1: N* is a completely different animal than the 4.9... The 4.9 uses a proprietary OBDI setup that has a lot of funky things going on...it's not just a simple serial data link. .

So does the early N* And the serial data link is what all the ECMs use to communicate. You will get alot of codes for the missing ECMs but you will be able to see the engine data. I have hooked up a 4.9 dash to a N* ecm the same way but they do not use the same codes. It would show codes for things that were not a problem.

quote Originally posted by Rickady88GT: I believe this is a Deville. My wire diagram says vin B?

Yes, it could be - 94+ Deville 4.9 are a bit different than the earlier ones, they also use the Seville type manifolds as well as the dual O2 sensors (forgot about those ones - my bad)

jscott1, send me an email to remind me (I usually forget these things by the time I get home), and I will see about digging up the diagrams for the HVAC and BCM.

hi guys;
thinking of going to heated sensors also but can't figure out whether to use lt1 or firebird sensors
does it matter which?
clynt

quote Originally posted by Fiero STS: So does the early N* And the serial data link is what all the ECMs use to communicate. You will get alot of codes for the missing ECMs but you will be able to see the engine data. I have hooked up a 4.9 dash to a N* ecm the same way but they do not use the same codes. It would show codes for things that were not a problem.

Okay, so it's just a serial data link... Hooking up the wires is the easy part. What's going through the wires is a different story. If all I get is a bunch of meaningless codes then what's the point? In order to be useful I would want to be able to control the system in the manner intended by Cadillac from the dash. Getting that to work without displaying all the codes for things that are not a problem is going to be problematic. Too much work for so little gain, is what I concluded after seeing the BCM was involved in the equation.

Tim - I have the Deville Factory Service Manual, so I probably have all the drawings...unless you got something above and beyond that?

You will see all the data that the sensors are putting out. Such as O2 voltage wether or not your in open or closed loop. You can data log from sensors.you can read rpms. You should be able to do anything that you would if the dash was in the car. The only fault codes that would be useless are the ones that are for things that wouldn't be hooked up on the data link. If you dont have a brake ecm you will get the fault for no brake data, If you don't have a rss ecm you will get a no rss data fault.

quote Originally posted by Fiero STS: You will see all the data that the sensors are putting out.

You make it sound so easy I'm tempted to give it a shot. What about the comment that I need the BCM and PCM from the same car? Is that neccessary? Considering that the BCM from my donor car has long since gone to Caddy heaven, I would rather just get a random BCM and hook it up. Would that work?

You do not need the BCM. Your dash will show that you have a BCM data error because it does not see it. Basicly think of the dash as a scan tool. It doesn't need all the ECMs to work, it will however display whatever info is availible on the data link wires. If you tied the BCM to the wires and powered it up you would get all the sensor data and fault data that the BCM has.

quote Originally posted by Fiero STS: It really is not that hard. I have done it for two N* cars. You can get a dash and the connectors at a u-pull for 25 bucks. Just make sure it is for your year 4.9. I have a 4.9 dash ( I thought it would work for a N*). It acctually worked but the data and faults were incorrect.

Thanks for all your help... Last time I went to the yard they had about a half dozen fresh Devilles. I'll have to schedule a trip there soon.

quote Originally posted by jscott1: N* is a completely different animal than the 4.9... The 4.9 uses a proprietary OBDI setup that has a lot of funky things going on...it's not just a simple serial data link. Fieroseverywhere - I would be interested in seeing the diagrams, just to see what's involved.

Sorry. Haven't been on here in a while. You are correct about the OB1 setup. Its been a real PITA to try to get working. I have the pages from the service manual scanned and in PDF format. Give me the word and I'll e-mail them to you. I hope someone can make this work.

Based on my research not only can you use the system as a scanner for error codes but you can actually do switch tests, switch/component cycling, sensor outputs including real time and logging and a host of other things that a scanner just can't do for this motor. As it works in the caddy's it's a COMPLETE diagnostic system for the entire car. Push a few buttons on the dash and you know how everything electronic is working. Can you 4.9 guys imagine pushing a few buttons and extending/retracting the ISC? Sure could have used feature while doing idle learn procedure....

I have everything in my e-mail ready to go already. Anyone who wants to look further into this please let me know.

[This message has been edited by Fieroseverywhere (edited 12-15-2008).]

quote Originally posted by Fieroseverywhere: Sorry. Haven't been on here in a while. You are correct about the OB1 setup. Its been a real PITA to try to get working. I have the pages from the service manual scanned and in PDF format. Give me the word and I'll e-mail them to you. I hope someone can make this work. Based on my research not only can you use the system as a scanner for error codes but you can actually do switch tests, switch/component cycling, sensor outputs including real time and logging and a host of other things that a scanner just can't do for this motor. As it works in the caddy's it's a COMPLETE diagnostic system for the entire car. Push a few buttons on the dash and you know how everything electronic is working. Can you 4.9 guys imagine pushing a few buttons and extending/retracting the ISC? Sure could have used feature while doing idle learn procedure....

Look at the dash connectors and see what pins are for the serial connector wires and the power and grounds. These are the only wires I have hooked up to my N* dash. Make sure you get the two tan data wires in the correct position you can get them crossed as they are the same color. I put in a 4 pin connector, kinda like a trailer light connector so I can plug in the dash. Then I put on some long leads so I can stretch around to the rear of the car or outside of it so I don't have to be in the car. You can also initiate the Idle learn proceedure, temporarily turn off the traction control, clear fault codes and a host of other stuff.

quote Originally posted by Fiero STS: Look at the dash connectors and see what pins are for the serial connector wires and the power and grounds. These are the only wires I have hooked up to my N* dash. Make sure you get the two tan data wires in the correct position you can get them crossed as they are the same color. I put in a 4 pin connector, kinda like a trailer light connector so I can plug in the dash. Then I put on some long leads so I can stretch around to the rear of the car or outside of it so I don't have to be in the car. You can also initiate the Idle learn proceedure, temporarily turn off the traction control, clear fault codes and a host of other stuff.

Its not that simple. I tried it and could not get even a flicker from the displays. First off the displays are tied into the whole setup. The display themselves run off of a 16V power source. The only reference for this is in the wiring diagrams where it looks like it comes from the BCM. Without lighting the displays you can't read anything on the displays. The displays are wired into the dash dimmer also. The display that allows you to access the system is the ECC (electronic climate control) display. This gives you some telltale signs but can't display actual data. The ECC ties into the FDC (fuel data center) which displays most of the data. In short you push the buttons on the ECC to display the data on the FDC. In addition to this there is something reffered to as the "programmer" that is wired into the system. I believe this is the black box under the dash but honestly don't know for sure.

There are two serial data wires that run between the PCM and BCM connecting the two. The PCM itself can't send the data to the displays. It mearly sends a signal to the BCM which decifers the signal and transmits the displayable data directly to the ECC and FDC to display. No joke, this system is complicated. The PCM handles all engine related sensors. The BCM handles all interior and some exterior sensors. Remember these caddy's have a ton of sensors including interior and exterior temp sensors, sun load sensor (for climate control/AC), AC high side/low side temp sensors, ect. Most of which are not even usable in the fiero. Unfortunately the BCM must be wired in to decifer the signal to be displayed.

In addition to the serial data connections there is a 5v reference wire that runs from the BCM, to the programmer, then from the programmer to the ECC, then off to the FDC. The serial data wire runs only between the BCM and PCM.

So minimum I figured I could get away with for the BCM was...

BCM to PCM serial data wires (one input, one output)
Power wires for BCM ( 2 battery, ign1 wire, ign3 wire)
2 grounds
16v output to displays
ECC output
FDC output
and power and ground for each display and the programmer along with data wires connecting all 5 components of the system.

However, when wire it up I don't get a single light. I'd be more then happy to send you the diagrams and info I have so you can take a look. If it was as simple as hooking up the serial data wires It would have been done months ago.

One thought I had later... Maybe since I am using a Fieroaddiction chip I'll need to find everything from a 91 deville. That is how my PCM chip is programmed.

Anyone confused yet?

[This message has been edited by Fieroseverywhere (edited 12-15-2008).]

I will look in my book for the 4.9 but I cannot imagine that the whole instrument cluster lighting, heater control etc. would change just because of a different engine. Maybe some program changes but I would not suspect much else. Just another note, I am using an analog gauge cluster not a full digital display. That might be where the extra 16v power supply and no visuals come from.

[This message has been edited by Fiero STS (edited 12-16-2008).]

quote Originally posted by Fieroseverywhere: Sorry. Haven't been on here in a while. You are correct about the OB1 setup. Its been a real PITA to try to get working. I have the pages from the service manual scanned and in PDF format. Give me the word and I'll e-mail them to you. I hope someone can make this work. Based on my research not only can you use the system as a scanner for error codes but you can actually do switch tests, switch/component cycling, sensor outputs including real time and logging and a host of other things that a scanner just can't do for this motor. As it works in the caddy's it's a COMPLETE diagnostic system for the entire car. Push a few buttons on the dash and you know how everything electronic is working. Can you 4.9 guys imagine pushing a few buttons and extending/retracting the ISC? Sure could have used feature while doing idle learn procedure.... I have everything in my e-mail ready to go already. Anyone who wants to look further into this please let me know.

what year and model is yoru service manual from? i was thinking about offering complete dash/bcm diagnostic kits in addition to my 4.9 chips, but i dont have any wiring info on the bcm nor the dash.. if i had that infrmation, it might be a viable kit i can construct for people - stickpony@gmail.com

quote Originally posted by stickpony: what year and model is yoru service manual from? i was thinking about offering complete dash/bcm diagnostic kits in addition to my 4.9 chips, but i dont have any wiring info on the bcm nor the dash.. if i had that infrmation, it might be a viable kit i can construct for people - stickpony@gmail.com

92-93 Deville/Fleetwood FWD versions only. Put me down on your list if you get it working. I have one of your chips also at the moment...