Q: Engine misfiring in a 2002 Pontiac Montana

asked by on December 29, 2015

I have an engine misfire and get Check Engine codes P0300, P0203, and P0204.

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A misfire could be caused by number of problems but since you are getting the p0204 and p0203 I believe that is is probably an injector that is causing the misfire. I would replace the injector for the number 3 and the number 4 cylinder and see if that fixes your problem. A mechanic with YourMechanic can assist you with that if you don’t feel comfortable.

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