I have a 90 Iroc and for a few years now the car hasnt moved because of a very strange issue that I cannot figure out. The car runs good when cold but as soon as it starts to gain some heat, It will die when you try to give it gas. I have replaced every single thing such as sensors(all of them), computer, distributor, fuel pressure regulator, map, you name it, its new except for the actual PROM. Not showing any codes right now but it did for awhile and if I remember correctly it was a #43 and a #12. The problem started years ago and would leave you stranded out of nowhere, but as soon as it cooled down, it would run normal again for awhile. It continued to get worse as time went on and now its constant when it gets warm. I feel like it is something about timing since when you try to rev it up, it wants to die down but will return to idle. Not letting the timing advance to handle the throttle? Distributor and coil or new. When the car is sitting at idle, it runs perfect, just cant take fuel. If you rev it up slow, its not so bad until the rpms get higher and sometimes you will get a little popping sound out of the exhaust. It the speed density injection system so to my knowledge, no spark control module to change. So what would control the ignition advance? Maybe not the problem, just my theory at this point. Fuel injectors are newer as well. I dont have an OBD 1 reader so is there a machine that I can read telemetry instead of just get codes? I hope its not a problem where a mouse chewed a wire or something strange like a grounding problem, etc. Whatever it is, its a brain teaser so I am reaching out for help. If I could find someone close, I would take it to them but you cant drive it on the road. Its an older car that is just a cool cruiser and isnt super nice, but cool and drives great when it runs. Please give me any input that someone may be able to help solve this annoying problem, it would be greatly appreciated.

 

What have you done with fuel pump and do you know it's not dying slowly?

 

Its been replaced so its kind of new. In my experience, they just die and not degrade slowly. I should check fuel pressure but you can hear it pump up when you turn the key on like it should and I have cracked the line and it squirts out everywhere. And I did put a good one in, a delphi I think.

 

QwkTrip made a valid point.
Have you monitored the Fuel Pressure while the Engine is running and stalling?

Generally issues with Cars are not fixed without Data/ Diagnostic Information.
So I recommend that you collect some.
Fuel Pressure information is one of the easiest to collect.

 

You need more data and less conjecture. Check fuel pressure with a fuel pressure gauge, check timing with a timing light. Gather a datalog with a moates cable or 1320electronics bluetooth adapter and a laptop with various software options, or a phone with aldldroid / the app from 1320electronics.

If you can reproduce the Code 43, follow the diagnostic procedure chart in the factory service manual.