Idle Control System: Notes
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 1990 Mitsubishi Van, 1990 Mitsubishi Sigma, 1990 Mitsubishi Pickup, 1990 Mitsubishi Montero, and 1990 Mitsubishi Mirage. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Idle Speed Control (ISC) motor used on DOHC engines controls a pintle-type air by-pass valve to regulate idle air by-pass volume. On SOHC engines, ISC motor adjusts throttle plate angle to regulate idle air by-pass volume.