Auxiliary Air Valve

The auxiliary air valve is used to increase airflow during cold engine starts and warm-up. It consists of a coiled bi-metallic sensor, bi-metallic sensor operated shutter valve, and an electric heating element for bimetallic sensor. At start-up, passing airflow is increased. As the engine temperature rises, airflow is decreased.

After engine start-up, heating is performed by the heater to which current is supplied from the fuel pump relay circuit. Shutter valve turns gradually to decrease airflow. After a certain elapsed time, the shutter valve is closed.