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Re: The P1391 Intermittent Loss of CKP/CMP
Posted to Technical Theory Forum on 12/4/2018

I wish I knew the algorithm and parametrics the PCM uses to judge CMP/CKP during cranking and during running.

The PCM is evaluating a P1391 during cranking as well as running - we could find no reason for its P1391 - nothing at all (other than maybe the sync... Login to read more.