The engine in a 1994 or 1995 Ford Mustang has an idle screw on the throttle body that adjusts how high or low the engine idles. This can be handy for fine-tuning your idle, particularly if it's idling lower or higher than the manufacturer recommends. This is also good if you prefer your idle higher or lower than the factory would like, for personal preference. Fortunately, this is a basic task, and can be done in just a few minutes with the help of a friend.
Pop the hood and locate the idle screw on the right side of the throttle body, just above the throttle linkage. Have your assistant start the car and sit in the driver's seat with the transmission in neutral or park, depending on if you have a manual or automatic transmission.
Turn the idle screw on the throttle body to the right to turn up the idle, or to the left to lower it. Have your assistant call out the RPMs listed on the gauge cluster as you adjust the idle up or down to your preference, or to between 500 and 600 RPMs, which is what the manufacturer recommends.
Turn off the car once the idle speed is where you want it. Drive the vehicle for 100 miles so the computer can learn the adjusted idle speed, then repeat the process if necessary.
