What are the faults of the throttle position sensor?
2 Answers
The faults of the throttle position sensor include: 1. Idle speed too high or too low; 2. Unstable idle speed, engine prone to stalling at idle; 3. Engine shaking during acceleration; 4. Delayed acceleration response; 5. Intermittent engine shaking during operation. The causes of throttle position sensor failure are: 1. Short circuit or open circuit of the idle switch; 2. Improper installation or adjustment; 3. Poor contact of the sliding contact of the linear variable resistor. The throttle position sensor, also known as the throttle opening sensor or throttle switch, is installed on the throttle body and is a device used to detect the engine's operating status.
As an experienced driver who has worked with many cars, the throttle position sensor is actually quite prone to issues. It's installed on the intake system and specifically monitors throttle opening. The most common problems include wear and aging of the sensor itself—over time, the internal electrical contacts may loosen or break, leading to inaccurate signals. There are also electronic component failures, such as a burned-out sensor chip, which can send erratic data to the ECU. Connection-related issues are also frequent, like loose connectors, corrosion, or damaged wiring harnesses, causing intermittent signals. The symptoms can be quite annoying, such as unstable idling, engine shaking, jerky acceleration, and in severe cases, sudden stalling or failure to start. For diagnosis, I usually use an OBD scanner to check for trouble codes—P0120 is a common one related to this issue. These tools aren't expensive, and you can even buy a simple one to try yourself, but it's best to get help from a knowledgeable friend or a repair shop.
