Mechanics

CHEVY RANDOM MISFIRE - CHECK ENGINE LIGHT ON

2005 Chevrolet Aveo

Engine Mechanical problem
2005 Chevy Aveo 4 cyl Two Wheel Drive Automatic 75000 miles

Please advise. Feel like we are being ripped off by local mechanics. Check engine light comes on often. Light reads random misfire error. We had a tune up and had the O2 sensor replaced but the light still comes on periodically, car jerks and sputters.

Were told to let the car warm up before putting into gear. Were told it may have to do with the HOLD button being engaged accidently. Were told it may be a coil problem.

I'm afraid my teenager will be stranded on the highway. Please advise.
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Vfayeparker
June 9, 2010.




P0300 Random misfires normally caused by vacuum leaks and bad fuel other causes below

1. Defective spark plug.
2. Inadequate spark/coil, defective spark plug wire.
3. Lack of compression
4. False air leakage.
5. Faulty fuel injectors.
6. Insufficient fuel pressure.
7. Contaminated fuel.
8. EGR valve that is leaking.
9. Oxygen sensors.

Tiny
Rasmataz
Jun 9, 2010.
These engines suffer mostly from leaking exhaust valves due to accumulated carbon deposits arround the area near the valve guides. There are modified exhaust valves with special groove near the valve head. Check the fuel trims on idle and if they are to minus value, valves' seats are the problem.
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Tiny
Spirov1610
Jun 13, 2010.

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