- Important Preliminary Checks

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 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 /System Diagnosis.
^ The scan tool data is within the normal operating range, refer to Scan-Tool Diagnostics / Typical Scan Data Values. Scan Tool Data List
^ Verify the customer concern, and locate the correct symptom. Check the items indicated under that symptom.