EG–478 ENGINE – 2JZ–GE ENGINE TROUBLESHOOTING VSV Circuit for ACIS CIRCUIT DESCRIPTION The circuit opens and closes the IACV (Intake Air Control Valve) in response to the engine load in order to increase the intake efficiency (ACIS: Acoustic Control Induction System). When the engine speed is 4,500 rpm or less and throttle valve opening angle is 30° or more, or engine speed is 4,500 rpm or more and throttle valve opening angle is 30° or less, the engine control module turns the VSV ON and closes the IACV. At all other times, the VSV is OFF, so the IACV is open. Throttle Valve IACV Actuator VSV Vacuum Tank Engine Speed ECM Throttle Valve Opening Angle Throttle Valve FI6612 VSV IACV ON closed OFF open WIRING DIAGRAM Engine Control Module B-R 3 EA3 B-R 2 1 G-Y 39 ACIS E9 GR 8 EA1 VSV for ACIS E01 B+ 2 2 EFI Main Relay R/B No.2 2 2 GR 24 M-REL E10 B-Y 2 R/B No.2 EFI No.1 W-B 2A B Battery FI5950