i have a code p1391 intermittent loss of cmp/ckp sens. the ckp sens is fed to both the tcm and pcm on this one. i scoped cmp @ pcm, ckp @ pcm, ckp @ tcm, and the ckp itself. cmp looked great. ckp, however, did not. i had dropouts and low voltage (3v). this was... Login to read more.