Idle Up Control Valve: Description and Operation

PURPOSE/OPERATION
The fast idle control device (FICD) allows additional air to bypass the throttle plate during air conditioning operation. When the A/C compressor is turned "ON," the ECM responds to the increased load on the engine and by energizing the fast idle solenoid. When energized, the solenoid opens an idle bypass passage, allowing additional air around the throttle valve and raising the idle speed. A fast idle adjusting screw regulates the amount of bypass air allowed when the solenoid is energized. A faulty fast idle solenoid does not set a trouble code.