Throttle Actuator Control (Tac) System

ENGINE CONTROL MODULE

The TAC module in this system is integrated into the ECM. The TAC achieves throttle positioning by providing a pulse width modulated voltage to the TAC motor after determining the drivers intent and then calculating the appropriate throttle response. The TAC module is not serviced and is to be replaced with the ECM.

The ECM controls all ignition system functions, and constantly corrects the basic spark timing. The ECM monitors information from various sensor inputs that include the following:
- The throttle position (TP) sensor
- The engine coolant temperature (ECT) sensor
- The mass airflow (MAF) sensor
- The intake air temperature (IAT) sensor
- The vehicle speed sensor (VSS)
- The transmission gear position or range information sensors
- The engine knock sensor (KS)