Circuit Description

Idle speed is controlled by Electric Throttle Control System (ETCS). ETCS is composed of throttle motor to operate throttle valve to connect throttle motor with throttle valve, throttle position sensor to detect opening angle of throttle valve, accelerator pedal position sensor to detect accelerator pedal position, ECM to control ETCS and one valve type throttle body. DTC is set when idle speed continues to vary greatly from target speed. Possible causes are:

• Electric throttle control system.
• Air induction system.
• PCV hose connection.
• Defective ECM.