Possible Causes
WARNING: This page is about a different car, the 2002 Nissan Xterra and 2002 Nissan Frontier. However, it is still accessible from the selected car via links, so may be relevant.
Malfunction is detected when mixture ratio compensation amount is too large (mixture is too lean or too rich). Possible causes are:
- Defective HO2S1.
- Defective injectors.
- Exhaust leaks.
- Fuel pressure incorrect.
- Defective Mass Airflow (MAF) sensor.
- Lack of fuel (DTCs P0171 or P0174 only).
- Intake air leaks (DTCs P0171 or P0174 only).
- Incorrect PCV hose connection (DTCs P0171 or P0174 only).