Idle Air Control (IAC) Valve
Idle Air Control (IAC) Valve DescriptionFunction
- The IAC valve controls the amount of the bypass air that passes through the throttle valve, IAC is controlled by a PCM signal.
- The air, which bypasses the throttle valve, flows through the IAC valve from inlet port (air hose side) to outlet port (intake manifold side).
Structure
- IAC valve is composed of a housing, plunger, coil and spring.
Operation
- When the IAC valve receives a signal from the PCM, the electric current is applied to the coil circuit. The plunger is then pulled back to allow bypass air into the outlet port.
- The bypass air flow is controlled by the period of time that current is applied to the coil circuit. This current opens the plunger, allowing bypass air into the outlet port.