5 SIGNS OF BAD THROTTLE POSITION SENSOR

The most common symptom of a bad throttle position sensor (TPS) is poor acceleration or rough idle together with a check engine light on your dashboard. If you have an automatic transmission you may also notice shifting issues. Other driveability issues are also common. Because the throttle position sensor is such an important part of the engine’s performance, it could result in many different symptoms.

1. Poor Acceleration

One of the most common signs of a defective throttle position sensor is delayed or poor acceleration. Delayed acceleration means that there is a considerable time difference between stepping on the accelerator and the actual acceleration of the vehicle.

If you also notice that the car judders when accelerating, this can be due to a damaged throttle position sensor.

2. Idle Surging

The term idling refers to the operation of the engine when the vehicle is not actually moving. If you notice that your engine fluctuates when idling, this may be due to an irregular air-fuel mixture, which is related to a faulty throttle position sensor.

If the ECM does not receive correct information from the throttle position sensor, the throttle will not function correctly, resulting in idle surging.

3. Check Engine Light

There are several sensors in a vehicle, and if one sensor is not working, the check engine light comes on.

Although the check engine light will illuminate for various other reasons, it is advisable to check the throttle sensor, especially if your car has poor acceleration and idle surging. If your check engine light is on and related to the throttle position sensor, it will most likely be a trouble code related to the sensor in the ECU. You can check it with an OBD2 scanner.

4. Sudden Surge while Driving at a High Speed

If you have an electric throttle body, one of the most dangerous effects of a defective throttle position sensor is a sudden increase in speed while driving at high speed on a highway. What happens is that the throttle in the throttle valve may close automatically, and if the driver presses the accelerator pedal too hard, the valve suddenly opens and gives the car a small speed boost.

This happens if the throttle position sensor is damaged and sends an incorrect signal to the throttle valve, causing it to open and close suddenly. 

5. Problem with Shifting Gears

A poor throttle position sensor causes a problem with acceleration, which in turn causes a problem with the automatic transmission.

The throttle position sensor does also sends information to the automatic transmission control unit. If this information is faulty, there might also be a problem with your automatic transmission’s shiftings.