A throttle body is a device that controls the amount of air that flows into an engine. It is a core component of any combustion engine vehicle, and its main duty is to control the air flowing into the engine. The throttle body is positioned between the air intake filter and the intake manifold. When the driver presses the accelerator pedal, the throttle plate (also known as the butterfly valve) inside the throttle body opens up to allow more air to enter the engine. This increased airflow draws more fuel into the engine, which then causes the car to accelerate. The throttle body can be found in different areas depending on a vehicles engine type. Older models usually feature a throttle body that is built directly into the carburetor, which is used for fuel injection. Late-model fuel-injected engines have a throttle body usually located between the intake manifold and the air filter. In electronically fuel-injected cars, a throttle position sensor and air-flow sensor communicate with the main electronic control unit (ECU), which supplies the corresponding amount of fuel needed at the injectors.