1998 Chevrolet Truck Repair Question
Mileage: 150,000 miles.
Chevrolet Truck Compression Problem
Asked by raymonddiannamathewsAnswer
compression test is a good start. get it checked.
get the back pressure checked for the cat converter as well. simple test to verify the engine can breathe
Roy
I checked the compression, it was aroun 80 psi but I was using a push in gauge so it minght be higher. I had the cat checked. it was good. The truck started to run better all by itself but still cuts out some on high rpm or when you romp on it. My new fuel pump only puts out 55 psi when i turn the key, 48 psi when ideling and 57 psi when you flip the throttle. the pressure holds with the key off, but is this pressure still to low? Also I read where a guy had simular problems and a new knock sensor solved it. Still no codes.
knock sensor would code.
fuel pressure is low, should be 60-65 lbs.
what was the back pressure on the cat?? how did you check it??
Roy
I had the muffler shop check it out, its a high flow cat installed 12 months ago. They put a hole in the exhast but i didnt see them use any kind of insterment. They said they would love to sell me another one but that one was good.
when should the fuel pressure at 60-65
ignition on without motor running ?
motor idling ?
motor accelerating?
Im not real clear on that.