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Idle Speed Control (ISC) Motor

Idle Speed Control (ISC) Motor:




The Idle Speed Control (ISC) motor is attached to the Throttle Body Fuel Injection (TBI) unit. The Powertrain Control Module (PCM) uses the ISC motor in order to control engine idle speed. The ISC motor consists of the following components:
^ A DC motor
^ A plunger
^ A gear assembly
^ A Closed Throttle Position (CTP) switch

The PCM controls the engine idle speed by running the ISC motor plunger forward or backward. The ISC motor plunger contacts the throttle lever screw in order to control the throttle valve opening. Forward movement of the ISC motor plunger increases the throttle valve opening and increases engine (idle) speed. Backward movement of the ISC motor plunger decreases the throttle valve opening and lowers engine (idle) speed.