Mechanics

CHEVY ENGINE STARTS AND REVS UP AND DOWN BY IT

1999 Chevrolet Express

Engine Performance problem
1999 Chevy Express V8 Two Wheel Drive Automatic 281000 miles

This van will crank up and run Ok sometimes, but when you put it in gear, it will rev up and down from idle to maybe 1000-1500 rpm own its own. If you try to drive forward and give it some throttle, it will stall out like getting too much gas. I think, but not sure that sometimes I smell gas like its getting rich on me or something. What do you guys think?
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Frankyc
April 28, 2008.




Check fuel pressure and get back to us.

Tiny
Mastertechtim
Apr 28, 2008.
I went out and bought a fuel pressure gauge and tested the fuel pressure and it was Ok, steady at 52, but the engine was steadier than it had been. At the same time, I bought a ignition tuneup set, dist. Cap, rotor, etc, and went to put on the cap and rotor to find that the screw holes for the cap had been busted on one side and stripped out on the other, making the cap sit high on the busted out side. That was the problem. Thanks though, I figured it was something to do with the fuel too, but glad the problem is found.

Tiny
Frankyc
May 6, 2008.
Very common for those to strip out. How did you fix it? Curious.

Tiny
Mastertechtim
May 6, 2008.
Creatively of course. Piece of coat hanger bent across the top attached to each side to hold it down tight enough so I could drive it to Marta inspection to get tags. Need to get that going as soon as possible. I guess I'm gonna get a new distributor and put it in. Just flippin the van for a little money though. Thing runs great as long as the motor is firing right, but a pool company trashed it inside, enough clay and dirt to grow corn in all over the floors, dash, you name it. Good work van if it's cleaned up.
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Tiny
Frankyc
May 7, 2008.
I usually see wire ties holding them on.

Tiny
Mastertechtim
May 8, 2008.
I thought it was the distributor cap but it looks like something else.
It will crank up and run great for a while and then it will go crazy, the speedometer goes nuts, the anti-lock brake light comes on, and it will run in lunges and then seems like it has died but if I take it out of drive into neutral it's still running and runs Ok, put it back into drive it lunges for a while and repeats the same deal. Seems like the gear shifting affects the problem. If you put it in 1st gear, it seems to still change gearsand will lunge so bad that the drive shaft sounds like it's coming apart. A mechanic locally put in a speed sensor in the transmission, ran Ok for a while and then started the same problem again.

There isn't an engine service light or code at all.

What could cause this?

Tiny
Frankyc
Aug 4, 2008.
I would use my scan tool and drive vehicle while watching the vehicle speed sensor reading from the transmission to determine if its computer related or dash cluster problem. Check all grounds on engine block and battery cable connections at battery.

Tiny
Mastertechtim
Aug 5, 2008.

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