Throttle Body: Description and Operation

The Throttle Body Assembly, controls airflow to the engine via a single or dual butterfly valve. The throttle position is controlled by conventional linkage. The body is a single-piece, die casting of aluminum. It has a single bore with an air bypass channel around the throttle plate.


Other features of the air throttle body assembly include:


1. an adjustment screw to set the throttle plate at a minimum idle airflow position,


2. a pre-set stop to locate the wide-open-throttle (WOT) position,


3. a throttle body mounted throttle position sensor,


4. a PCV fresh air source upstream of the throttle plate (some applications)


5. individual vacuum taps (some applications) for PCV and EGR control signals.


6. idle air bypass valve.