Mechanics

CAR STUMBLES/STUTTERS/HESITATES UPON ACCELERATION FROM DEAD STOP OR INCREASING SPEED SOMETIMES

2003 Chevrolet Venture • 75,000 miles

New fuel filter, newplugs/wires/o2 sensor, dry gas, injector cleaner, no codes, certified mechanic found no misfires in computor history, 52psi gas pressure gauge reading engine off key on, 55psi at idle, 58/59psi on accelaration to say 50mph, even stumbles/hesitates at 58/59psi. Could it be coils? Fuel pressure regulator holds vacuum ok, sometimes it runs fine. Van has electronic egr. Depressing on accelerator when stumbling causes engine to perk up and car gets going. With brakes locked and gas pedal floored rpm changes by around 500rpm about.
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Ronbo1
March 17, 2012.




Very doubtful coils at fault since no misfires.

Tiny
Fixitmr
Mar 17, 2012.
Does it feel sound like misfiring or just loss of power?

Tiny
Fixitmr
Mar 17, 2012.
Needless to say, live data monitoring would help zero in on issue.
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Tiny
Fixitmr
Mar 17, 2012.
Does not sound like misfire. Is loss of power. Surges up and down I would say about 4-500rpm approx it has no tach. We used to say it was "breaking up" when u get on the gas.

Tiny
Ronbo1
Mar 17, 2012.
Live data monitoring would be advantageous. Wonder if auto chain stores can do that?

Tiny
Fixitmr
Mar 18, 2012.
I am giving up on it and dropped it off at the chevy dealer this evening. Hopefully I wont have to take out a second mortgage to pay them if they can find out the problem. Thanks for ur help.

Tiny
Ronbo1
Mar 19, 2012.
Let us know how it goes.

Tiny
Fixitmr
Mar 19, 2012.
Dealer says it s catalytic converter plugged wants 1300.00 bucks lolo takin to a mom and pops to see what he says.

Tiny
Ronbo1
Mar 21, 2012.
If it isnt a cat maybe look at a pressure control solenoid. Causing a shudder under load when hot. Pretty common problem with the transmission in your van.

Chevyforlife
Apr 4, 2012.

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