What is the primary function of a throttle body in a fuel injection system?

The primary function of a throttle body in a fuel injection system is to regulate the amount of air entering the engine. This regulation directly impacts how the engine performs, as the amount of air that enters the combustion chamber influences engine speed and power output. In a fuel injection system, the air-fuel mixture must be carefully balanced for optimal combustion efficiency. The throttle body controls this air intake by adjusting the position of the throttle plate based on the driver's input and engine management system commands.

While it may also indirectly influence fuel delivery since the amount of air mixed with fuel is crucial for the engine's performance, the throttle body's main role is focused on managing airflow. Other components in the fuel system work in conjunction with the throttle body to ensure that the correct amount of fuel is injected relative to the air entering the engine.