4 Runner 2WD L4-144.4 2366cc 2.4L SOHC (22R-E) (1990)
Auxiliary Air Valve (Idle Speed): Description and Operation
Auxiliary Air Valve
The Air Valve, located on the underside of the Throttle Body, provides additional intake air around the throttle valve when the engine is cold. This
raises the engine idle speed until the engine can idle normally on its own. The Air Valve has a thermo wax sensor that stays in contact with engine
coolant and blocks off the bypass air passage as coolant temperature rises to normal operating temperature.