Throttle Body: Description and Operation

PURPOSE
- The throttle body meters airflow to the engine during idle, part throttle, and wide open throttle conditions.

OPERATION
- The throttle body controls air flow to the engine through a butterfly type valve. The throttle position is controlled by a progressive opening throttle linkage.

- The bypass channel controls both cold and warm engine idle flow as regulated by an Idle Air Control (IAC) valve that is mounted directly to the throttle body. The IAC valve meters airflow around the throttle plate in order to control engine idle speed.

- Engine coolant is diverted through the throttle body mounting pad to improve cold weather operation.

CONSTRUCTION
- The throttle body housing assembly is a single piece of aluminum casting. It has a singe bore with an air bypass channel around the throttle plate.