IACV Control 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 60° or more, the IACV is open (VSV: OFF). At all other times, the IACV is closed (VSV: ON).

Fig 1: Identifying Throttle Valve Opening Graph

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.