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Auxiliary Air Valve

The auxiliary air valve provides additional air during cold engine starts and warm-up. 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 air flow stops. See Fig 1 .

Fig 1: Auxiliary Air Valve By-pass channel closes as engine temperature rises.
G34489