Conditions For Setting DTC

Engine coolant temperature is more than 140°F (60°C).
Engine is operating in closed loop.
Engine has been running at least one minute.
Canister purge duty cycle is less than 10 percent.
Engine speed is between 1500 and 3000 RPM.
Mass air flow is between 18 and 42 g/s.
Above conditions are present for 3 seconds.
90 seconds after closed loop and stoichiometric operation have been achieved, the PCM monitors the oxygen sensor as it switches above and below 450 mV. If fewer than 23 rich-to-lean and lean-to-rich switches are detected, DTC P1133 will be set.