1. Locate the idle air control valve (IAC valve) on the throttle body. The IAC valve is usually a black or gray cylinder-shaped component with a wire connector attached to it.
2. Disconnect the electrical connector from the IAC valve.
3. Use a flat-head screwdriver to loosen the two screws that hold the IAC valve in place.
4. Once the screws are loose, you can turn the IAC valve to adjust the idle speed. Turning the valve clockwise will decrease the idle speed, while turning it counterclockwise will increase the idle speed.
5. Start the engine and let it idle for a few minutes.
6. Check the idle speed with a tachometer. The idle speed should be between 600 and 900 RPM.
7. Adjust the IAC valve accordingly until the desired idle speed is achieved.
8. Tighten the screws that hold the IAC valve in place.
9. Reconnect the electrical connector to the IAC valve.
10. Test-drive the vehicle to make sure that the idle speed is steady and that there are no other driveability issues.
