Idle Speed Control

ECM controls engine idle speed according to engine operating conditions and component/model application. ECM will send a signal to the Idle Air Control Valve-Auxiliary Air Control (IACV-AAC) valve to adjust and compensate for idle speed under the following conditions: from starting to 20 seconds after start, low battery voltage, engine overheating, electrical load, A/C on, power steering load, during deceleration and when vehicle is moving at idle.