When Monitored

This diagnostic runs once per ignition cycle when the following conditions are met:

• Shortly after an initial engine start.
• The difference between the coolant temperature and ambient air temperature is greater than 15°C (59°F) at initial engine start.
• The engine coolant temperature recorded at the last engine shut down was above 83°C (181.4°F).
  NOTE:

  If the previous engine shut down temperature was not above this value, the shut down diagnostic will not be performed during this ignition cycle.

• There was a minimum of 10°C (50°F) temperature drop during the last ignition off.
• If the above monitoring conditions are met, the PCM uses the engine coolant temperature drop to calculate a maximum ignition off time threshold. It then compares the previous ignition off time to the calibrated maximum threshold.