Idle Air Control Valve

Bad Idle Air Control Valve Symptoms

The idle air control (IAC) valve controls the idle speed of fuel injected vehicles and takes control of engine rotational speed only when your foot is off the accelerator. The idle speed is determined by engine temperature and is controlled by your vehicle's engine control unit. Often the idle air control valve is only in use when the engine is idling and has not yet reached operating temperature, ensuring that the fuel and air mixture is appropriate while the vehicle is warming up. When your vehicle's IAC valve or actuator is failing, it can cause issues such as rough idling or stalling, and in some cases, a high idle if the valve is stuck in the open position and allowing too much air into the engine. If the valve is stuck shut, it can also cause a lack of airflow into the engine at idle, which may lead to stalling. Depending on how little air is flowing through the valve, this may occur after the engine has warmed up, or it may stall immediately after it starts. Over time, contaminants may also accumulate in the IAC valve chamber, which can cause the valve to clog or jam. It's also possible for the valve's solenoid, seals, or other electrical components to fail, preventing it from operating as it should. This will often trigger a Check Engine light, and you can stop your local O'Reilly Auto Parts for free Check Engine light testing to help determine the source of the problem. For your next IAC valve repair, shop O'Reilly Auto parts, where we carry an assortment of new idle air control valves for most vehicles.