Hey guys new to this site, been lurking for a bit though.

Now before I get to far into this I did try searching this problem and found a couple things from other posters but nothing that seemed to help. So here I go. Car is a 92 Firebird 3.1 153,XXX miles

About 2 weeks ago, when I got home a put the car in park and it stalled, at the time, I didnt really try to restart it(I work 12 hour overnights and just wasnt to concerned with it) but then 2 days later my wife tried to take it and she started it up and it stalled right away. and then it wouldnt start again.


So the next day I did some research, and went to check a few things. I tested the ohms on the injectors as that was one the things I read on here, they ohmed out fine, although I know they could still be plugged or something. I also disconnected the front line from the fuel filter just to see how fast fuel coming from there and from my experience it seemed to be flowing ok. I tested spark and everything seemed to be sparking ok. Now what I did notice was both the vacuum lines from the MAP sensor were disconnected and there was a giant gaping hole in my stock intake tube. So I reconnected the MAP lines and replaced the intake tube. I tried starting it after that and got it started again and it stalled right away. But then when I started it again I gave it some gas and it would accelerate and stay at any RPM I held the throttle at without any issue. But if I let off the throttle, it will idle for approx. 2-5 seconds fine and then stall. Anyone have any Idea what the problem could be? Ive read it could be the IACV or a couple other things, but im hoping someone can maybe narrow it down to a couple of things rather than the 10 or so I can think of.


Sorry for the long winded post!! Any help would be greatly appreciated!

 

Hey, i used to have a 2.8, and this happened a couple times and my problem was timing. You might have great spark but if its not sparking at the right time she wont stay running

 

You almost certainly need to remove/check/clean the IAC (Idle Air Control) valve. Clean the passages. Also, pull the vac line from the fuel pressure regulator and smell for gas in that line and/or look for drips. If either you need to replace the diaphragm in the regulator.

 

I did also check the line from the FPR to the TB. It didnt drip or smell like gas. But I did smell the dipstick and that smelled a little like gas, but I wasnt sure if it was from the FPR being bad or if it was from my wife possibly flooding it the day she couldnt get it started.

 

1. Vacuum leak. Find it and fix it.
2. Disconnect the battery and reconnect it to reset the ECM.

If it ran fine (or somewhat fine) before this, don't waste time on the IAC. You can take it off and clean it, but it's probably a waste of time.

3.1s also have a nasty ignition problem related to the wiring harness...

 

hi, had the same problem on my car for ages, turned out the garage that fitted the spark plugs did not gap them right and that was making it stall. ran fine everywhere else though - quick thing for ya to check anyhows. good luck !