Misfire problems. Please help
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My car developed a misfire. Changed plugs and wires. No.1 plug was very black. Misfire was still there. Long story short, did compression test, checked rockers, vacuum leak, fuel pressure, swapped no.1 and no.3 coils then injectors and no.1 plug still turns black right away. Misfire still there. Any ideas? BTW, according to the laser thermometer, that header pipe is 90 -100 degrees cooler than the rest.
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From the diagram they all share the same ground so look for an open on the ground side cause its the easiest thing to do and then check for a signal from the PCM to the coil. Maybe check resistance values on both ground and power. Hope you can figure it out before you have to leave.
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It is getting spark. It just seemed weak. Used a screwdriver to check that. I feel as if all my bases are covered, but still have the problem. Guess turbomach is gonna have to bring his diagnostic tool from work.
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Found it...Broken valve spring. Why do it seem like all aftermarket head manufacturer use **** valve springs anymore, GM seem to have the same trouble, with some of there springs too.