Circuit/System Verification
WARNING: This page is about a different car, the 2008 Buick LaCrosse and 2008 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition ON, observe the scan tool DTC information. Verify there are no other DTCs set.
- If there are other DTCs set refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.
- Engine at normal operating temperature, observe the scan tool Total Fuel Trim Avg. parameter. The parameter should display between -22 to +23 percent.
- If not within the specified range, verify that none of the following conditions exist:
- A mass air flow (MAF) sensor signal that is skewed-If the Short Term FT parameters for both banks changes greater than 20 percent when the MAF sensor is disconnected, refer to DTC P0101 for further diagnosis.
- Inspect for a collapsed air intake duct
- Inspect for a restricted air filter element. Refer to Air Cleaner Element Replacement
- Inspect the MAF sensor for foreign objects. Refer to Mass Airflow Sensor/Intake Air Temperature Sensor Replacement
- Inspect for restricted exhaust system. Refer to Symptoms - Engine Exhaust
- Inspect for excessive fuel in the crankcase. Change the oil as necessary
- Rich fuel injectors-Refer to Fuel Injector Balance Test with Special Tool or Fuel Injector Balance Test with Tech 2
- Incorrect fuel system pressure-Refer to Fuel System Diagnosis
- Fuel that is contaminated-Refer to Alcohol/Contaminants-in-Fuel Diagnosis (w/o Special Tool) or Alcohol/Contaminants-in-Fuel Diagnosis (w/ Special Tool)
- Contaminated HO2S-Silicon
- If not within the specified range, verify that none of the following conditions exist:
- Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.