Throttle Body: Description and Operation

Throttle Body And Attachments:

The throttle body houses the throttle valve (used to meter air to the engine) and the idle air bypass passages. It also serves as a mounting platform for the idle speed control servo (stepper motor type) and the throttle position sensor. The idle speed control servo is an ECU controlled device used in the idle speed control system and the throttle position sensor is an input sensor utilized by the ECU in determining engine operating conditions.
Since both the idle speed control servo and the throttle position sensor are ECU related devices, for description of operation and testing procedures refer to COMPUTERIZED ENGINE CONTROLS.