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2009 Pontiac G6 Question: I have a p0301. Have changed the spark plugs and rotated coils to rule them out.
Answer #1pushrod January 11, 2014, 09:26Master
Check for vacuum leak and injector pulse. Plug wet when removed? If so, check compression. Seems we have quite a following here, hope you get it fixed!
Answer #2Diesel Cecil January 11, 2014, 10:12Rookie
I'd start looking at the injector or injector wire harness
Replypushrod, January 11, 2014, 10:29Master
Boy i sure wish i had thought of THAT!!! Do you know what injector pulse is?
Answer #3cardocIII from Gillespie's Auto Service, January 11, 2014, 12:39Master
When does the misfire occur? At idle? Under a load? Or all of the time? Is it constant or does it come and go?
Answer #4G. T. Service Center (4242 Answers) , Stephenville, TX - (254) 638-3236ProfessorG January 11, 2014, 13:56Master
Try the intake induction service, Per GM Bulletin.
Answer #5Dr Quick January 11, 2014, 17:20Enthusiast
Just rotating the coils will not show up a miss fire, as it will just move to another cylinder. Try disconnecting one coil at a time when engine is running. If when a certain coil is disconnect there is no difference in engine missing, you have found a bad coil.
Replypushrod, January 12, 2014, 00:30Master
It will change the misfire code if coil is defective and switched to another cylinder!