Question about 2002 Chevrolet TrailBlazer

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I have a misfire in cylinder #2 on a 2002 chevrolet trailblazer, with an 4.2L 6cylinder. I've changed the spark plugs and put a new coil in. It Still runs rough. What else could it be?

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If you do not have a vacuum leak these are know for clogging injectors. They are buried and require a couple hours labor just to access and replace it. Or you can have an injector service performed by a shop. It'l run you 100 bucks give or take and doesnt always fix it. Or you can run some additive strong in the fuel tank and hope for the best. Or if your strapped and have plenty of time you can swap # 2 injector with 3 or so and see if the code follows. This is alot of work but it will rule out an intake gasket issue possibly.

Posted on Nov 18, 2009


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