The function of the mechanical throttle body is the same as the electronic throttle body. The difference is that the opening is not controlled by a signal from the ECU, but by a pull cable connected to the gas pedal. This means that the pedal’s position is directly related to the door plate pivot on the throttle. The position of the spool is transmitted to the ECU via a position sensor mounted on the throttle body, and the ECU ratios the fuel supply to the intake volume based on the position of the spool to achieve optimum economy, power, and emissions.
Compared with the electronic throttle, its control precision is low, and it cannot realize the vehicle cruise control, automatic transmission control, electronic stability control (ESP) of the body, and other functions. Idle speed control also can only be assisted by the stepper motor. But, it has the advantage of low cost, so it still has a greater demand under the condition of requiring low emission standards.
Click to learn the information about how electronic throttle body works?
