- Important Preliminary Checks

Before Starting Perform the Powertrain OBD System Check before using the Symptom Tables, and verify all of the following are true:
Testing and Inspection

^ The PCM and Malfunction Indicator Lamp (MIL) (Service Engine Soon) are operating correctly.

^ There are no DTCs stored.

^ Ensure that the engine coolant temperature is not above 130°C (266°F). This condition causes the PCM to operate in Engine Coolant Over temperature-Fuel Disabled Mode. While in Engine Coolant Over temperature-Fuel Disabled Mode, the PCM turns the fuel OFF to three cylinders at a time in order to keep engine temperatures from reaching damaging levels. The system perceives Engine Coolant Over temperature as a lack of power, miss, or rough idle. If the vehicle is operating in Engine Coolant Over temperature. Fuel Disabled Mode, refer to Cooling System for diagnosis.

^ The scan tool data is within the normal operating range, refer to Engine Scan Tool Data List.

^ Verify the customer concern, and locate the correct symptom in the table of contents. Check the items indicated under that symptom.