2003 Chevy Avalanche PO300 MISSFIRE CODE

2003 CHEVROLET AVALANCHE
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ROBINSLACK
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  • 2 POSTS
Engine Mechanical problem
2003 Chevy Avalanche V8 Two Wheel Drive Automatic

i am getting a po300 missfire code, and have no fire to cylinders 1,3,5,7, the cylinders are firing , but are missfires
May 9, 2010 at 8:44 PM
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RASMATAZ
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Engine running rough or misfiring can be cause by the following:

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.
May 9, 2010 at 10:25 PM
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ROBINSLACK
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we have done a compression check, changed mas sensor, map sensor, new pulgs, checked oxygen sensor, still missfiring and running lean, all the problems started when I was going down the interstate, and put the truck on cruise control, could my electronic trhottle body be the culprit.
May 15, 2010 at 11:30 AM
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