Auxiliary Air Valve

The 924-S and 944 (except 944-S) use an auxiliary air valve to provide additional air during cold engine starts and warm-up. It is located next to throttle body. The valve consists of an electrically heated bi-metallic strip, movable disc and air by-pass channel. The heater coil on the bi-metallic strip is energized by the fuel pump relay.

Control of the valve is based upon engine temperature. The air by-pass channel is open when engine is cold and gradually closes as temperature rises. At predetermined temperatures, air by-pass channel is blocked and additional airflow stops.