Identify the idle adjustment screw in the carburetor or throttle body. This screw is usually located on the side or top of the carburetor or throttle body.
Warm the engine up until the thermostat has opened. This will ensure the engine is running at its normal operating temperature.
Once the engine is warm, turn the idle adjustment screw clockwise to increase the idle speed, and counterclockwise to decrease the idle speed.
Adjust the idle speed to the recommended value, which is usually around 750-850 RPM. This value can be found in the vehicle's repair manual.
Make sure the engine idle is stable and does not fluctuate.
If the idle speed is too high, the engine will run rough and stall. If the idle speed is too low, the engine will stall when you put it in gear.
Once the idle speed is set correctly, turn off the engine and let it cool down.
