Engine Controls - Self-Diagnostics: Summary
If no Diagnostic Trouble Code (DTC) is present but a driveability problem still exists, proceed to appropriate TROUBLE SHOOTING - NO CODES article for symptom diagnostic or intermittent diagnosis procedures.
After confirming that the circuits and components of a suspect system are functioning properly and clearing DTCs, the ECM PROM may require replacement if DTCs reset. Replacement procedure not available from manufacturer.