Possible Cause
NOTE:
The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- A/F sensor (sensor 1) malfunction/slow response
- A/F sensor (sensor 1) circuit range/performance
- Fuel system too lean
- Fuel system too rich
- Secondary HO2S (sensor 2) circuit signal stuck lean
- Secondary HO2S (sensor 2) circuit open
- Secondary HO2S (sensor 2) slow response
- Air/fuel ratio variation between cylinders
- Misfire
- Exhaust system failure (exhaust gas leak)