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Circuit Description

This circuit opens and closes the Intake Air Control Valve (IACV) in response to the engine load in order to increase the intake efficiency (ACIS: Acoustic Control Induction System).

When the engine speed is 4,700 rpm or more and the throttle valve opening angle is 60Ω or more, the VSV is OFF, so the IACV is open. All the other times, the ECM turns the VSV ON and closes the IACV.

Fig 1: Circuit Description
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