Hey guys,
vehicle is 88 trans am gta long time fan of these cars and I finally got my first one. Long story short I put a new tranny in, fired it up and my car ran much better than what I started with (was getting 5 codes before) but check engine light came on again. Did the paperclip trick I learned on here to pull codes and got codes 36 and 42 which I was getting to begin with. My mistake was forgetting to pull the paperclip out before starting my car again, now it runs worst than before as it won't even stay on. I know it's ok to run the car in open loop with the paperclip in but from what I understand that should be done only after starting the car. So I'm just wondering if anyone can tell me if I burnt my ecu? Did I short it? Any help would be much appreciated and thank you.

 

If you left the paper clip in and started the car the ecm goes into field service mode. Im sure no harm is done.

 

Man I hope you're right, now I just gotta figure out why it wont stay on unless i give it throttle, I dont think the above codes would cause it to die since they didn't before. Thanks Tuned

 

I would start with the code 36 diagnostic first. Grounding the diagnostic port just puts the ecm in a field service mode. that's just like starting it with a 10k ohm resister across a to b to enable data flow for a scanner or laptop.

http://chevythunder.com/maf_code_36.htm

 

Thats perfect tuned, I've been looking for something like that. I already tried changing the relay twice (kragen and napa) relays and even tried switching with the power relay and fan relay as I've read they are the same. Problem doesnt go away .so been thinking trying a relay from the dealer.I read on another thread that having the relay with the exact part number will make a difference. Imma trouble shoot with that link you sent sent before I buy anything now. As for it running like hell now and not staying on, I was thinking last night. Do you think because its pretty low on gas (3 bar on a digi dash) and at an angle (got the rear on ramps) its not getting enough fuel through the system thus not staying on?? Thanks for all your help so far

 

The fuel pump pickup is at the back of the tank so even on ramps its submerged. With the trouble codes showing your ecm is in limp home mode and will run poorly.

 

Dam so much for the easy fix, was looking at the diagram form the link it mention to ground the ground wire going to the relay (while the relay is connected) any suggestions on how I should do that, should I just cut it? I'd hate to do that since I can't solder but I will

 

If your asking about were it says probe the wire with a test light hooked to ground. You are checking for power. A vom on cd or test light will work to see if you have power.

 

No im referring to the step that says "reconnect relay, disconnect MAF sensor, ground relay sensor terminal F, probe MAF sensor harness terminal D". so its telling me to reconnect the relay and ground out terminal F but since the relay is connected do I now have to cut the black wire ground out terminal F or is another way im not thinking of?? I got the car to run better today it actually stay on now but with a rough idle, I also noticed it runs better with the MAF disconnected I heard this means the MAF is bad??

 

When I fried my ecm, the car wouldnt even catch, it would crank and never fire, sounds more like you fried a sensor or relay if you have it running and dying/rough idle.

 

Well heck I followed the diagram and it looks like my ecu is bad, say tuned can you point me to another diagram for the ignition module code 42 says it could be a bad ecm, just want to confirm before pulling the trigger on one

 

http://chevythunder.com/est_code_42.htm
If you need one I have one left for $60 shipped in the lower 48

 

Thanks tuned, found a broken wire at the icm and noticed the egr selenoid was not plugged in properly took care of that and car runs better but not 100%. However according to chevythunder the white wire is shorted to a ground somewhere. However now I have no codes and the car still runs rough. Got two questions if you don't mind 1. If I unplug the MAF and the car runs better does that mean the MAF is bad 2. The canister purge valve has two hoses coming from it one goes to the TB and the other is plugged, is this correct? If not where should it go? Thanks for all your help so far