Intake Air Control Valve
WARNING: This page is about a different car, the 2003 Lexus SC 430, 2003 Lexus LS 430, 2003 Lexus IS 300, 2003 Lexus GS 430, and 2003 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.
- Install a 3-way vacuum "T" fitting in vacuum hose between Intake Air Control Valve (IACV) actuator and ACIS Vacuum Switch Valve (VSV). See Fig 1. Connect a vacuum gauge to vacuum "T" fitting. Start engine. With engine idling, ensure vacuum is not present.
- Snap accelerator to Wide Open Throttle (WOT). Ensure vacuum reading momentarily reads about 9.8 in. Hg and IACV actuator rod pulls down. If vacuum is not as specified or actuator rod fails to pull down, go to next step.
- Remove IACV. Apply about 15.8 in. Hg to IACV actuator. If IACV actuator rod does not move, turn adjusting screw on IACV assembly. If IACV actuator rod still does not move, replace IACV actuator. If IACV actuator rod moves, check to see if diaphragm holds vacuum for at least one minute. If diaphragm does not hold vacuum, replace IACV actuator. If diaphragm holds vacuum, check vacuum tank. See ACIS VACUUM TANK .