Tech Support Forum - View Single Post - [SOLVED] 95 Chevy S-10 4.3L TBI

**qldit** · 09-03-2007, 05:01 AM

Good Evening dgoad, it is not uncommon when engines have vacuum leaks to find exhaust valves get a little burned, which could well be your problem.
I would suggest a comprehensive compression test with all plugs removed recording all pressures and then repeating the test on each cylinder after adding a few CC's of oil down each plug-hole. Once again record pressures.
Any notable variation spread initially may tell you something and any reasonable variation between non-oiled and oiled readings would suggest rings may have a problem.

Low fuel pressure can also cause this kind of effect, what is the book pressure for that machine?
I wouldn't expect any large spread with the engine running, it kind of suggests to me that the fuel availability is a bit short.

Regardless of any suggestion it sounds like you are going to have to spend on the thing.

Isn't it exasperating when one of these things won't idle nicely!

Cheers, qldit.

09-03-2007, 05:01 AM	#2 (permalink)
qldit TSF Gearhead Join Date: Mar 2007 Location: Brisbane Australia. Posts: 592 OS: All Systems, mainly Linux	Re: 95 Chevy S-10 4.3L TBI - Idle troubles Good Evening dgoad, it is not uncommon when engines have vacuum leaks to find exhaust valves get a little burned, which could well be your problem. I would suggest a comprehensive compression test with all plugs removed recording all pressures and then repeating the test on each cylinder after adding a few CC's of oil down each plug-hole. Once again record pressures. Any notable variation spread initially may tell you something and any reasonable variation between non-oiled and oiled readings would suggest rings may have a problem. Low fuel pressure can also cause this kind of effect, what is the book pressure for that machine? I wouldn't expect any large spread with the engine running, it kind of suggests to me that the fuel availability is a bit short. Regardless of any suggestion it sounds like you are going to have to spend on the thing. Isn't it exasperating when one of these things won't idle nicely! Cheers, qldit.