6000 V6-173 2.8L VIN W FI (1986)
Idle Speed/Throttle Actuator - Electronic: Description and Operation
Fig. 5 Idle Air Control (IAC) valve
The Idle Air Control (IAC) Valve is located in the throttle body unit and is used to control engine idle speed. The valve operates by allowing air to
bypass the throttle valve in the throttle body unit. If engine RPM is too low, the ECM will move the IAC conical valve in to allow more air to bypass the
throttle valve. If engine RPM is too high, the ECM will move the IAC conical valve out to allow less air to bypass the throttle valve, Fig. 5. If IAC
connector is removed with the engine running, the idle set RPM may be lost. To reset idle set RPM, turn ignition On, then Off.
