chr1s

I'm having an odd issue with my 1996 Trans Am. It will start up and idle perfectly fine on a cold start. It runs and drives after that for a good 20 minutes or so, but once it warms up it starts acting up at highway speeds. It will sometimes backfire and die. Then once it dies or I turn it off after it's already warmed up it's a struggle to get it started again. I've replaced the opti and MAF already but I'm definitely no mechanic so if anyone could help me with this I would appreciate it. If there's any troubleshooting I could do to determine what it is just let me know.

Thanks,
Chris

Tainted

iTrader: (9)

a few things

1. wrong lt1 section
2. mileage
3. plugs/wires ever changed?
4. potential fuel issue. how old is your filter and pump?

steveo_

ICM heat related failure maybe - try spacing it (and the coil) out from the head by stacking some washers in there, to see if it gets better.

chr1s

I figured out the issue with the misfire and dying at high RPMs. It was carbon build up in the throttle body. I got all that cleaned and it runs and idles perfectly when warm. But there is still a starting issue. And like I said before, that's only an issue when it's warmed up. It will start perfectly fine when it's cold. I plugged in a computer and it throws a Coolant Temperature Sensor code. Could that be it? I replaced it not too long ago and checked the connector for voltage, seems to be working fine.

Tainted

iTrader: (9)

that shouldnt give it trouble starting up. since the TB was so dirty have you ever cleaned the MAF?

chr1s

Yes I purchased a brand new MAF and cleaned out the throttle body really good. Now it just has the starting issue. Can't figure it out.

ahritchie

iTrader: (1)

What kind of opti did you use? Codes? Most of the parts store ones are crap, best to go AC delco or MSD... seems like opti to me:

Symptoms:

* Car suddenly dies and won't restart
* Starts but immediately dies
* Extended cranking to start
* Rough idle
* Sputtering
* Backfiring
* Trouble reaching higher rpm
* Black smoke from exhaust
* Poor performance with car warmed up
* Weak plug wire spark
* Codes 16, 36, and 42 may be set ??????

Read more: http://www.gmhightechperformance.com...#ixzz2uMC9oXhw

Jr.Samples

I had the exact problem. As a few members have already mentioned check you plug wires. I did all the other things mentioned but when I got the plug wired changed it disappeared.

Good luck.

Huntr1117

iTrader: (18)

Check the ICM as someone stated before, could also be the starter. Id check the ICM 1st