Thermostatic Air Cleaner: Testing and Inspection

Air Cleaner Assembly:

The thermostatic air cleaner system consists primarily of two components, these are: the vacuum operated air regulator flap and the temperature control valve.

TAC Flap:

AIR REGULATOR
The Air regulator controls the amount of warm and cold air quantity entering the air cleaner. It should be covering the warm air intake when the engine is not running.
1. Remove the air cleaner upper housing.
2. Disconnect the vacuum hose from the air regulator actuator port.
3. Connect a hand operated vacuum pump to the air regulator actuator port and apply vacuum. The actuator should move smoothly uncovering the warm air inlet and sealing the cold air inlet.
4. If the actuator fails the test, it should be replaced with the lower air cleaner housing.


TEMPERATURE CONTROL VALVE
The temperature control valve controls the amount of vacuum applied to the air regulator actuator.
1. Remove the the vacuum hoses from the sensor ports.
2. Connect a hand operated vacuum pump to the upper port and apply vacuum. The valve should not pass air when the engine compartment is warm. It should pass air when cold.
3. If the valve fails either test, the valve should be replaced.