For a car to run smoothly, it needs the proper mixture of air and fuel. The amount of air in the engine is controlled by the air intake system. A throttle body is part of the air intake system that helps control the amount of air that gets into the engine. The throttle body has a throttle plate. If the plate is closed, it prevents the air from getting into the engine. When you push the gas pedal, it opens the plate, allowing the air to enter the engine. The amount of air depends on the position of the plate, which is controlled by the gas pedal. The harder you push the gas pedal, the wider the plate will open, and more air will flow to the engine. This means more power and more speed. The throttle position sensor reports the position of the gas pedal to the computer in your car (Engine Control Unit). The computer then determines the position of the throttle plate. It also calculates the amount of air flow to the engine and the amount of fuel to be injected for the required ratio of air-fuel mixture.