P1391 Intermittent Loss of CMP or CKP

SYMPTOM
P-1391 INTERMITTENT LOSS OF CMP OR CKP

WHEN MONITORED
Engine running or cranking.

SET CONDITION
When the failure counter reaches 96 for 2 consecutive trips.

POSSIBLE CAUSES
- CKP connector observable defect
- CKP sensor connector terminal(s) observable def
- CKP sensor signal ckt wir harness intermittent def
- CMP and CKP wiring harness intermittent defect
- CMP connector observable defect
- CMP sensor connector terminal(s) observably def
- CMP sensor signal ckt wiring harness inter def
- PCM black connector observable defect
- Distributor rotor or rotor drive system loose
- Flywheel defective
- Camshaft position sensor defective
- Crankshaft position defective (flywheel)
- PCM connector terminal(s) obser def (CKP sensor)
- PCM connector terminal(s) obser def (CMP sensor)