Throttle Position Sensor: Description and Operation

- A throttle position sensor is provided with a potentiometer which is interlocked with the throttle valve shaft.

- This throttle position sensor sends the ECM a potentiometer output signal corresponding to the opening of the throttle valve. When the level of this signal exceeds a predetermined value, the ECM interprets it as complete closure of the throttle valve and makes a control most suitable for the engine operation with the throttle valve fully closed. For correcting error of this signal, the ECM is provided with a learning function.

- Thus, the ECM precisely controls the air-fuel ratio during acceleration and deceleration as well as engine idling.