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Discussion Starter · #1 ·
I'm seeing random misfires at idle. Not on one cylinder but while scanning for about a minute, I had at least a couple misfires on every cylinder except #2. The weird thing is that I don't see misfires while under load. I did a 950+ line scan from my house to my office (about 5 minutes, in traffic with stop signs and lights and all) and got misfires on random cylinders but none while the engine had any load. Any thoughts?

I smashed 2 plugs a couple weeks ago during normal street driving and I'm trying to find the cause before I rebuild without fixing the problem and scrap another engine. I'm lost and don't know what else to look for. Any other ideas?
 

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Joe, most likely it's caused by your changed idle due to your cam. They aren't actual misfires; the PCM just thinks they are misfires. The S1X cam I would think is a large enough cam to cause this, but I could be mistaken.
 

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Most likely your smashed plugs were casued by broken piston ring lands. From what I've read, ususally caused by detonation.
 

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Discussion Starter · #4 · (Edited)
I agree 10,000%. I HAVE broken ringlands and those broken pieces DID smash my plugs. This is fact. I need help tracking down the cause of this detonation or whatever caused this so I don't tranfer this problem to the new engine.

EDIT- Oh yeah, I agree with Jason. The stage1X isn't big enough to trip a multiple misfire code but it is still big enough to show a few misfires.
 
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