Throttle Body: Description and Operation

The throttle body assembly is attached to intake manifold. The throttle body is used to control air flow into engine, thereby controlling engine output. The throttle valve within throttle body is opened by driver through accelerator controls. During engine idle, throttle valve is almost closed, and air flow is handled by Idle Air Control (IAC). The throttle body also provides location for mounting Throttle Position (TP) sensor and provides a manifold vacuum source for various components. Vacuum ports are located at throttle valve to generate vacuum signals needed by various components.