Symptoms of a Faulty Throttle Pedal Position Sensor?
3 Answers
Symptoms of a faulty throttle pedal position sensor are as follows: 1. A broken throttle pedal position sensor can cause the throttle to become uncontrollable because the throttle body can no longer receive signals indicating the opening size, or there may be no response when accelerating. 2. If one or both sensor signals are interrupted, the fault memory will record a fault, and the electronic throttle fault light will turn on. Comfort functions such as cruise control or engine torque adjustment will be disabled. 3. If the two sets of resistors inside the sensor cannot detect each other, the ECU cannot obtain the correct current position of the throttle pedal, leading to symptoms like weak engine acceleration. A failure in one set of resistors in the potentiometer may cause the ECU to receive incorrect signals.
As someone who frequently repairs cars, I've found that the most obvious sign of a throttle sensor issue is when there's no response after pressing the accelerator, or the response is extremely slow, making the car seem like it's gasping for air. Sometimes the tachometer jumps up and down on its own, and even though your foot hasn't moved, the car speed fluctuates between fast and slow. Last time, a car's engine just roared when the accelerator was pressed, but the speed didn't increase, and it even stalled suddenly twice, which was terrifying. Such faults should never be ignored, as they can lead to electronic throttle errors, uncontrolled acceleration, or even brake assist failure. Older cars, in particular, should be checked for connector oxidation or wiring damage from rodents.
With over a decade of driving experience, I've personally encountered throttle sensor failure: At a red light turning green, pressing the accelerator yielded no response while horns blared behind me. A panicked restart finally got the car moving. Later, I noticed that after driving for over an hour, the accelerator pedal felt like stepping on cotton—inconsistent and unreliable. The most dangerous incident was during a highway overtake when the throttle suddenly dropped to zero; thankfully, I managed to pull over in time. The mechanic explained that worn sensor resistance plates cause intermittent signals. Now, during every maintenance check, I have them plug in the diagnostic tool to inspect the throttle data stream.
