Air Intake Control Circuit: Description
WARNING: This page is about a different car, the 2010 Toyota Camry. However, it is still accessible from the selected car via links, so may be relevant.
The air cleaner is equipped with two inlets, one of which is opened or closed by the Air Intake Control Valve (AICV). This system reduces intake noise and increases engine power at low-to-high engine speeds range.
When the engine is operating in the low-to-mid speed range, this control operates the AICV to close one of the air cleaner inlets. When the engine speed is more than 3,600 RPM and the opening angle of the throttle valve is more than 60°, the ECM activates the VSV and opens the AICV.