LEMON Manuals: Even more car manuals for everyone
Home >> Chrysler >> 2002 >> Neon LX, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P1398: Misfire Adaptive Numerator At Limit >> Testing

DTC P1398: Misfire Adaptive Numerator At Limit: Testing

NOTE: Check for any Technical Service Bulletin (TSB) that may apply to this DTC.
  1. Turn the ignition on. With the DRBIII(R) in Engine Misc, select Clear PCM Battery Disconnect to reset the PCM. With the DRBIII(R), select the Misfire Pretest. Road test the vehicle and relearn the adaptive numerator. The adaptive numerator is learned when the Adaptive Numerator Done line on the Misfire screen changes to Yes. Did the adaptive numerator relearn? If yes, go to next step. If no, go to step  3 .
    2. WARNING: When the engine is operating, DO NOT stand in a direct line with the fan. DO NOT put your hands near the pulleys, belts or fan. DO NOT wear loose clothing.
  2. Conditions that set DTC are not present at this time. The following list may help in identifying the intermittent condition:
    • With the engine running at normal operating temperature, monitor the DRBIII(R) parameters related to the DTC while wiggling the wiring harness. Look for parameter values to change and/or a DTC to set.
    • Review the DRBIII(R) Freeze Frame information to identify under what conditions the DTC set.
    • Refer to any TSB that may apply.
    • Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or partially broken wires.
    • Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals.

    Were any of the above conditions present? If yes, repair as necessary. If no, test is complete.

  3. Turn the ignition off. Visually inspect CKP sensor wiring harness. Look for chafed, pierced, pinched or partially broken wires. Visually inspect CKP sensor harness connector for broken, bent, pushed out or corroded terminals. Ensure CKP sensor is properly installed and mounting bolt(s) tight. Refer to any Technical Service Bulletin (TSB) that may apply. Were any problems found? If yes, repair as necessary. If no, go to next step.
  4. Remove the CKP sensor. Inspect the tone wheel/flex plate slots for damage, foreign material or excessive movement. Were any problems found? If yes, repair or replace the tone wheel/flexplate as necessary. If no, go to next step.
  5. There are no possible causes remaining, replace CKP sensor.
scientia non olet · About LEMON Manuals