Which component adjusts the flow of air to the engine?

The throttle body is the component responsible for adjusting the flow of air into the engine. It acts as a valve that opens and closes based on the position of the accelerator pedal. When the driver presses the pedal, the throttle body opens to allow more air into the intake manifold, which in turn increases the engine's power output. This precise control of air flow is critical for proper air-fuel mixture, which directly affects engine performance and efficiency.

The fuel injector, while essential for delivering fuel to the engine, does not control the air flow. The air filter serves to clean the incoming air by trapping dirt and debris, but it does not adjust the air flow. The intake manifold is responsible for distributing the air-fuel mixture to the engine cylinders, but again, it does not control the air flow itself; that function lies with the throttle body.