Monitor DTC Status
NOTE:
If any TPS, MAFS or ISCA Valve circuit codes are present, do ALL REPAIRS associated with them before proceeding with this troubleshooting tree.
- Connect scan tool and select "Diagnostic Trouble Codes (DTCs)" mode.
- Press F4 (DTAL) to select DTC information from the DTCs menu.
- Confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions
- Read "DTC Status" parameter.
- Is parameter displayed "History (Not Present) fault"?
- History (Not Present) fault: DTC occurred but has been cleared.
- Present fault: DTC is occurring at present time.
YES : --> Fault is intermittent caused by poor contact in the sensor's and/or ECM's connector or was repaired and ECM memory was not cleared. Thoroughly check connectors for loose or poor connections, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
NO : --> Go to next step as below.
CHECK FOR RESTRICTED INTAKE OR EXHAUST SYSTEM
- Visually/physically inspect the following items:
- Air cleaner filter element for excessive dirt or for any foreign objects
- Throttle body inlet for damage or for any foreign objects
- Restricted exhaust system
- Was a problem found in any of the above areas?
YES : --> Repair as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
NO : --> Go to next step as below.