By-Pass Valve (Federal Only)

Located between the air pump and the air distribution manifold, the by-pass valve controls secondary air flow. The purpose of the by-pass valve is to prevent afterburning during deceleration. This is accomplished by cutting secondary air flow to the exhaust system when high intake manifold vacuum is sensed at by-pass valve. Secondary air is diverted to atmosphere. This prevents additional burning of rich fuel mixture caused when throttle blades close initially upon deceleration.

Fig 1: LUV Air Injection System for Federal Vehicles

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Fig 2: Sectional View of By-Pass Valve (Federal)

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Fig 3: LUV Air Injection System for California Vehicles

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Fig 4: Sectional View of Mixture Control Valve (Calif.)

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