1992 Chevy Suburban Fuel delivery problems?

MALECAT

MEMBER
1992 CHEVROLET SUBURBAN
V8
2WD
AUTOMATIC
250,000 MILES

I have a 1992 Chevrolet Suburban 5.7 TBI. It will run fine some days no problems. Other days it will die and not restart. It doesn't matter if it is hot or cold. It will only die when you are coming to a stop or trying to sit at an idle. You can drive it on the highway and it will be fine. When you exit onto the offramp and come to a stoplight/stopsign it will die. You can shoot starting fluid into the air cleaner and it will restart from the fluid but not idle. If you start it with starting fluid and hold it at 1500 or 2000 or more rpm it will stay running but the moment you try to let off the throttle to let idle it will die again. You have to do this five, ten, maybe thirty times, start it with starting fluid and hold it at 1500 plus RPM. Then all of a sudden it will idle again and you can drive away until the next time it acts up. I just replaced the fuel pump, filter and relay and it did not help the problem. When it is running it runs strong with no missing or hesitation. The SES/MIL is not lit.

1 Reply

MASTERTECHTIM

MECHANIC
4,750 POSTS

Sounds like the idle air control valve is stuck closed causing idle speed to be too low. If engine is running smooth then suspect idle air control valve. How to tell easy is use the accelerator pedal as the valve. Will it run if you slightly press on pedal? Just enough to keep it at 800 rpms? If yes then replace valve and I would also with your mileage actually remove the throttle body to clean carbon from passage ways under throttle body and install a new gasket, this is vbery easy to do and is cheap main tainance. I usually find the passage ways cloggedwith carbon.