what does an idle air control valve do
by HowStuffWorks.com Contributors. An idle air control valve, also called an idle air sensor control motor, is an electrically operated valve that controls the amount of air that bypasses the throttle plate in cars with a fuel injection system [source: Autozone ]. This causes the idling speed of the engine to change as needed.
How does an idle air control valve work. Many people are confused about how idle air control valves work. An idle air control valve literally bypasses air around a closed throttle plate so the engine can get air at idle. Because it bypasses air, itâs also called an air bypass valve. Back in the days of carburetors, idle speed was adjusted by way of an idle speed screw.