Normal Mode: Notes
WARNING: This page is about a different car, the 2007 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
During the operation of the throttle actuator control (TAC) system, several modes or functions are considered normal. The following modes may be entered during normal operation:
- Learned idle mode-When ever the powertrain control module (PCM) recognizes the learned idle throttle position (TP) value, the engine operates in the learned idle mode. In the learned idle mode, the PCM uses stored engine performance settings in order to provide the best quality idle for all idle speed situations.
- Learned idle TP values-The TAC module relies on a stored TP sensor value for optimum idle speed operation. After PCM replacement or PCM reset, a new TP sensor value is learned and stored in the PCM memory. Refer to the Idle Learn below.
- Cold engine start mode-The throttle valve has a default start position that ensures improved cold engine starting and cold engine operation. In the cold engine start mode the TAC module commands the throttle control motor to the default position. In case of a TAC system malfunction, the default position spring opens the throttle valve to the default position.