Red Seal Automotive Service Technician Practice Exam

What is the function of a throttle position sensor?

1. To measure fuel pressure

2. To provide voltage regulation

3. To measure the position of the throttle valve

4. To affect exhaust flow

The correct answer is: To measure the position of the throttle valve

The throttle position sensor plays a crucial role in the operation of an internal combustion engine. Its primary function is to measure the position of the throttle valve, which is responsible for controlling air intake into the engine. By accurately determining how far the throttle valve is open, the sensor provides essential input to the engine control unit (ECU). This information allows the ECU to adjust fuel injection and ignition timing accordingly, optimizing engine performance, improving fuel efficiency, and ensuring proper emissions control. Understanding the position of the throttle valve is vital for the ECU to manage engine power and responsiveness effectively. When the driver accelerates, the throttle opens wider, and the sensor relays this information to the ECU, which then increases fuel delivery to match the demand for power. Conversely, during deceleration, the throttle closes, signaling the ECU to reduce fuel injection. This precise coordination between the throttle position sensor and the engine management system illustrates the importance of the sensor in maintaining optimal engine function and performance.