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Air Injection System: Operation

The air injection pump delivers fresh air to diverter valve whenever the engine is running. See Fig 1 . Fresh air is switched by the diverter valve, to the catalytic converter or air filter according throttle position. Calif. models direct air to catalytic converter only during idling and coasting conditions. Federal models direct air to catalytic converter only during idling, coasting conditions and up to a throttle angle of 4°. See Fig 2 .

Fig 1: View of Diverter Valve
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Fig 2: View of Throttle Body
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