Conditions For Setting DTC
- No related DTCs.
- Engine coolant temperature is 140°F (60°C) or more.
- Engine is operating in closed loop.
- Engine has been running at least one minute.
- Canister purge duty cycle is 10 percent or more.
- Engine speed is between 1500 and 3000 RPM.
- Mass air flow is between 18 and 42 g/s.
- Above conditions are present for a 3 second monitoring period.
- Ninety seconds after closed loop operation has been enabled, Bank 1 HO2S No. 1 transition ratio between lean-to-rich and rich-to-lean is less than 0.44 or more than 3.8.