Chrysler PT Cruiser 2001 Service Manual Supplement page 2633

Symptom:
P1398-MIS-FIRE ADAPTIVE NUMERATOR AT LIMIT
When Monitored and Set Condition:
P1398-MIS-FIRE ADAPTIVE NUMERATOR AT LIMIT
When Monitored: Under closed throttle decel with A/C off, ECT above 23°C (75°F), and
more than 50 seconds after engine start.
Set Condition: One of the CKP sensor target windows has more than 2.86% variance from
the reference window.
DAMAGED TONE WHEEL/FLEX PLATE (CRANKSHAFT)
CKP SENSOR CONNECTOR/WIRING
CRANKSHAFT POSITION SENSOR
IMPROPERLY INSTALLED/LOOSE CRANKSHAFT POSITION SENSOR
TEST
1 Turn the ignition on.
With the DRBIII , read DTC's.
Is the Good Trip Counter displayed and equal to zero?
Yes → Go To 4
→ Go To 2
No
2 Note: Check for any TSB's that may apply to this symptom.
Read and record the Freeze Frame Data. Use this information to help you duplicate
the conditions that set the DTC. Pay particular attention to the DTC set conditions,
such as, VSS, MAP, ECT, and Load.
Turn the ignition on.
With the DRB in the miscellaneous menu, choose Clear PCM battery disconnect to
reset the PCM.
With the DRB, choose the Mis-Fire Pre-test screen.
Road test the vehicle and re-learn the adaptive numerator.
The adaptive numerator is learned when the Adaptive Numerator Done Learning
line on the Mis-fire Pre-test screen changes to Yes .
Did the adaptive numerator re-learn?
Yes → Go To 3
→ Go To 4
No
POSSIBLE CAUSES
ACTION
173
DRIVEABILITY - GAS
APPLICABILITY
All
All