1. Locate the idle air control valve (IAC). It is usually mounted on the throttle body.
2. Start the engine and let it reach operating temperature.
3. Turn off the engine.
4. Disconnect the electrical connector from the IAC valve.
5. Use a 5/16-inch Allen wrench to turn the adjustment screw on the IAC valve clockwise until it stops.
6. Reconnect the electrical connector to the IAC valve.
7. Start the engine and let it idle.
8. If the idle speed is too high, turn the adjustment screw counterclockwise until the desired idle speed is reached.
9. If the idle speed is too low, turn the adjustment screw clockwise until the desired idle speed is reached.
