Adjusting the RPM of the idle air control system on an engine is necessary to keep the engine operating efficiently. The idle air control system should be adjusted routinely to keep the system running properly and get the best performance from the engine. You can adjust the idle speed adjustment screw on the system with a screwdriver and vacuum gauge in just a few minutes.
Locate the idle speed adjustment screw of the idle air control system on the air intake pipe. Remove the rubber vacuum hose from the vacuum port on the intake pipe and connect a vacuum gauge to the port.
Start the engine and adjust the RPMs of the idle air control system with a screwdriver. Turn the adjustment screw counterclockwise a quarter turn at a time until the engine begins to stall out and turn the adjustment screw back clockwise a quarter turn.
Set the RPMs by turning the adjustment screw clockwise a quarter turn at a time with the screwdriver until the vacuum gauge reaches the highest RPMs possible with the engine running smoothly.
Turn the adjustment screw back counterclockwise a quarter turn and disconnect the vacuum gauge from the vacuum port. Fasten the vacuum hose to the port and turn off the engine to complete the RPM adjustment.
