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WR Auxiliary Air Valve - Part # 035 133 453 A/C/E

The auxiliary air regulator allows more air/fuel mixture when the engine is cold in order to improve driveability and provide idle stabilization. The increased air volume is measured by the air flow sensor and fuel is metered accordingly. The auxiliary air valve contains a specially shaped plate attached to a bi-metal spring. The plate changes position according to engine temperature, allowing the most air to pass when the engine is cold. As temperature rises, the bi-metal spring slowly closes the air passage and the valve should close completely when the engine is at operating temperature. The bi-metal spring is also heated electrically, allowing the opening time to be limited according to engine type.


Note: The engine must be cold to start this test

Quick test: Pinching the upper hose together completely should affect idle when the engine is cold but not when it is hot.

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