Variable Induction Control Actuator: Description and Operation

The high speed inlet air control (HSIA) solenoid controls the vacuum applied to the inlet air shutter valve actuator. The IAC solenoid applies vacuum to shutter valve at low (RPM) which holds the shutter valve closed, and vents the shutter valve actuator vacuum to atmosphere above 5000 RPM to allow the shutter valve to open. The IAC solenoid is controlled by an output signal from the electronic control assembly.