Throttle Body: Description and Operation

Throttle Body:

The intake manifold and throttle body are integrated into a single aluminum casting. Runner lengths are tuned to optimize engine torque and power output. The manifold provides mounting flanges for the Idle Air Bypass (IAB) valve, Throttle Position (TP) sensor and Positive Crankcase Ventilation (PCV) tube. Vacuum taps are provided to support various engine accessories.

The throttle body assembly controls airflow to the engine. The throttle position is controlled by a single butterfly-type valve. The throttle position is controlled by a conventional cable/four bar throttle linkage. The body is a single piece die casting made of aluminum. It has a single bore with an air bypass channel around the throttle plate. This bypass allows both cold and warm engine idle airflow as regulated by an IAB valve assembly mounted directly to the throttle body. The valve assembly is an electro-mechanical device controlled by the Electronic Control Assembly (ECA). It incorporates a linear actuator which positions a variable area metering valve.