DEFINITION: The engine fails to reach the normal operating temperature. Cool air is felt from the heater.

Coolant level or mixture incorrect.

Check the coolant mixture and add coolant as necessary.

Thermostat malfunction - stuck in the open position.

Inspect and replace the thermostat. Refer to Engine Coolant Thermostat Replacement .

Cooling system passages restricted

1. Remove the obstruction.
2. Flush the cooling system as required.
3. Refill with coolant. Refer to Cooling System Draining and Filling .

Incorrect temperature gage reading

Check the temperature gage for proper operation. Connect a Scan Tool to the vehicle and read the system temperature. Compare this reading to the temperature gage. Replace the gage if necessary. Refer to Fuel/Temperature Gage Replacement .

Loss of system pressure

Check the following areas for possible leakage:

Pressure check the system and cap. Ensure the correct cap is being used.