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Had this thing come in for a complaint of a flashing check engine light while driving. Intermittent, and when it got to us light was on steady. Customer says the engine had no misfire while driving. Ran perfect, just a flashing light. P0300 was the only code. Drove vehicle and no misfires to be felt. Scan data for misfire shows counting on all cylinders while at 2500 rpm. At idle there is no counting. I decided to see what cam sync was at in data and found it to be around 11 degrees. Scope on cam and crank signals at pcm and you can see the results in the attached file. Based on past captures of these engines, I have a mechanical timing problem, stretched chain perhaps. Anyone have any input?
"The man who says it cannot be done should not interrupt the man doing it."
Last edit: 7 years 8 months ago by JoesAutoElectric. Reason: cannot get attachment to upload
Hey sir! I'll happily take a look at your waveform.
This generation of 4.0L is distributorless, right? You probably tried setting the sync with the scanner, any luck/improvement?
I've *heard* that these CMP sensors can be installed backwards and flag false misfires as a result, but I've never seen it personally. Any evidence someone has been here before you?
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