Throttle Body: Description and Operation

Throttle Body Assembly:

DESCRIPTION
The throttle body assembly controls intake air quantities. It consists of:
- Aluminum housing
- Throttle plate
- Throttle Position (TP) sensor
- Idle Air Control Bypass Air (IAC BPA) valve

OPERATION
The idle air control system supplies small quantities of air during engine idle by bypassing air past the throttle body plate. This system consists of the IAC BPA valve made up of the Idle Air Control (IAC) valve and Bypass Air (BPA) valve. The TP sensor is mounted on the LH side of the throttle body. It detects the throttle body plate position and provides the Powertrain Control Module (PCM) with that information.