Mechanics

CHEVY CYLINDER MISFIRE

2003 Chevrolet Avalanche

Computer problem
2003 Chevy Avalanche V8 Four Wheel Drive Automatic 89000 miles

What would cause #4 & #6 cylinders to misfire at the same time. And suggestions for repair
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Carl Kingsbury
June 29, 2008.



Possible bad head gasket, bad injector wiring, bad PCM, bad plug wires, injectors need to be cleaned. Most likely a vaccum leak at the intake manifold. There can be a whole list of things. Did you check to see if thre was spark at the plug wires and injector pulse at the fuel injectors. Also check for a vaccum leak at that point of the intake

Tiny
Rhall77
Jun 30, 2008.