THE BEECHMONT CREST AUTOMOTIVE LEARNING ZONE
ENGINE THROTTLE VALVE
This is a butterfly valve within the throttle body assembly. It controls airflow and gasoline engine power output.
When the engine throttle valve is closed, it restricts the amounts of air and fuel that flow into the engine. This reduces engine speed and power output, so that the engine idles.
When the driver engages the gas pedal, the throttle cable opens the throttle valve. Air rushes into the intake manifold. Engine sensors detect the change, and increase fuel flow through the injectors. More air and fuel flow into the cylinders, increasing engine speed and power output. This, in turn, causes the the vehicle to accelerate.