Throttle Plate - PFI: Description and Operation

Throttle Posittion Sensor:

THROTTLE BUTTERFLY

The Throttle Butterfly is located between the plenum chamber and the Mass Air Flow Sensor. The throttle butterfly is linked directly to the accelerator pedal and controls the volume of air entering the plenum chamber. As the accelerator pedal is depressed, the throttle butterfly opens. This reduces the restriction of air flow and allows a greater volume of air to enter the plenum chamber.