P1398

Tests 586 - 589:

Tests 590 - 593:

SYMPTOM
P-1398 MIS-FIRE ADAPTIVE NUMERATOR AT LIMIT

WHEN MONITORED
Under closed throttle deceleration; A/C off; engine coolant temp above 75 deg; longer than 50 seconds after engine start. Speed at which deceleration occurs must be sufficient for given gear range; eg, above 36mph in 1st gear or above 65 mph in high gear.

SET CONDITION
When one of the CKP sensor target windows (40 degrees) has more than 2.86% variance from the reference window.

POSSIBLE CASES
- Slots in flexplate defective
- CKP sensor defective
- CKP sensor not properly installed
- CKP sensor visibly defective
- Notches in crankshaft defective