Circuit/System Testing
WARNING: This page is about a different car, the 2010 GMC Sierra and 2010 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- Verify none of the following conditions exist:
- Lean or rich fuel injectors-Refer to Fuel Injector Diagnosis (CH47976) or Fuel Injector Diagnosis (J39021 or Scan Tool)
- Water intrusion in the HO2S harness connector
- Low or high fuel system pressure-Refer to Fuel System Diagnosis (Without FPCM) or Fuel System Diagnosis (FPCM)
- Fuel that is contaminated-Refer to Alcohol/Contaminants-in-Fuel Diagnosis (Without Special Tool) or Alcohol/Contaminants-in-Fuel Diagnosis (Special Tool)
- Fuel saturation of the evaporative emission (EVAP) canister
- Exhaust leaks near the HO2S
- Engine vacuum leaks
- Engine oil consumption-Refer to Oil Consumption Diagnosis
- Engine coolant consumption-Refer to Loss of Coolant
- If you find any of the above conditions, repair as necessary.
- If all conditions test normal, test or replace the appropriate HO2S.