Patient: 1995 Z28

Problem: Drive home from work and the engine's running fine. Shut engine down after getting home. Next morning it won't keep running.

Specifics: The car will fire up but it won't maintain idle. It runs poorly with low vacillating rpm and eventually dies. When I turn the key I can hear the fuel pump whir and then stop, as it should, after a few seconds.

If I blip the throttle I can keep it running but once I stop blipping it slows down and quits running.

I also can't rev it above 2500-3000. It seems to be starved for fuel. Got about an 1/8 of a tank of fuel.

I've attached a Dlog from Scan94/95 for those who know what to look for. No DTCs have been thrown.

 

Without even looking at the log, your probably going to want to start by checking fuel pressure.

 

Does your AIR pump still work? The flag shows the relay is on, and the O2 sensor readings are very low (lean). If the pump is working, that's normal, if the AIR is not operative, shows a lack of fuel.

In any case, I would check the fuel pressure.

You do realize that 1/4 tank on the gauge can mean as little as 1 to 2 gallons in the tank?

 

I've removed the air pump. I'll check fuel pressure.

 

With no AIR pump actually operating, looks like it's getting barely any fuel at all, based on O2 sensors.

 

I'll check fuel pressure first including the regulator check, but it's probably due for a fuel pump. 140,000+ miles and 20 years on the original pump. I've changed the frame mount fuel filter recently.