How to Find Symptoms of a Bad Throttle Position Sensor?

Are you noticing engine issues in your car? But it’s difficult to figure out why. And in case you noticed the issue surrounding your car accelerates or idles, then it’s a clear sign of a bad  throttle position sensor. However there can be other possibilities also but most commonly it happens due to TPS.

Scraply bring the complete informative guide where we will know more in details on what are the symptoms of bad throttle position sensor, it’s causes, and ways to deal with it. 

Let’s get into it!

What is a Throttle Body Sensor?

The Throttle Position Sensor is one of the crucial parts of your vehicle. It’s usually located right on the part that controls how much air should go into the engine. Throttle body sensor also called Throttle position sensor (TPS).

This helps the car’s to monitor how much power it wants, so it can adjust things like fuel and air mixture to make the engine run smoothly. More advanced versions of throttle body sensors are used in cars. 

Signs of a Bad Throttle Position Sensor

This crucial part of the vehicle also becomes faulty sometimes, which decreases the performance of your overall vehicle. But how do you find when your car throttle body sensor is having an issue? Here are the top five signs of bad throttle position sensor:-

  1. Engine Issues: 

If your car’s throttle position sensor goes bad, your vehicle’s engine may have trouble in few ways:

The car’s bad throttle position sensor (TPS), you probably notice your car’s engine acting strange such as engine idling poorly. It includes the engine stalling or stop, and after starting there is low idle or the accelerator pedal is pressed while stalling.

The fluctuation of idle speed can also be because of dirt. 

  1. Acceleration Issues

Another sign that indicates a bad throttle sensor is accelerating issues. You may notice difficulty accelerating smoothly, or unresponsive acceleration due to incorrect signals from TPS. 

  1. Difficulty starting the engine

A bad throttle body sensor can make it difficult to start your engine, as it might not send the right signals to the engine monitor to adjust fuel and air mixture properly.  

  1. Poor fuel economy

When the throttle body sensor isn’t working properly, it can lead to inefficient fuel and mixture resulting in decreased fuel efficiency and higher fuel consumption. 

  1. Check Engine Light activation

Check engine light activity can alone signal minor or major issues. However, if engine light shows symptoms like rough idling or acceleration problems, it often indicates issues related to throttle body sensor. 

The light comes on when the ECU (Engine control unit) detects irregularities in throttle body sensor readings, prompting a diagnostic scan to identify the issues. If you notice the light along with these signs, it’s good to visit the mechanic to check for TPS (Throttle Position Sensor) issues. 

  1. Limp-home Mode Activation

If your car goes into limp-home mode, where it limits speed and switches off other non-essential functions. Through limp home mode activation it could indicate a problem with the throttle position sensor (TPS).

Cause of Bad TPS malfunction

A throttle body sensor usually has approx 5 years of lifespans, but it’s not just age that can cause problems. Electric faults or issues with the sensor’s wiring can also lead to failure and the symptoms mentioned earlier. Here are some common reason why your throttle position sensor might fail:

  • Wear and Tear over time: 

Overtime, the throttle body sensor may get wear and tear, which can reduce its accuracy. Environmental elements such as extreme temperatures or contaminants can also contribute to the sensor’s deterioration. 

  • Electric Problem: 

Sometimes, bad throttle body sensors can cause electric issues such as faulty wiring or loose connections that can disturb communication between the throttle body sensor and the ECU (Electric control unit). This can lead to incorrect signals or no signals at all, that can lead to erratic performance.

  • Incorrect Voltage Supply:

Bad throttle can lead to incorrect voltage supply which means that the sensor might not be getting the right amount of electricity it needs to work properly. Such as trying to use a flashlight with weak batteries – it just won’t shine as brightly.

Importance of Addressing a Bad Throttle Position Sensor

If your car is having a bad throttle position sensor, addressing them on time is crucial because it affects your car’s overall performance, safety, and emission. By addressing such issues before you can prevent further damages to your car, and ensure accurate diagnostic checks. Fixing it keeps your driving experience comfortable and smooth.  

Additional Tips to Maintain Throttle Position Sensor

Maintaining your car’s throttle body sensor is crucial for essential engine performance. Here are some tips to keep a TPS in good condition:

  1. Regular Inspection: For any signs of wear, damage, or corrosion regularly check the TPS. Such as – look for rough wires, loose connections or buildup of dirt and dust. 
  2. Keep It Clean: By using a sensor- safe cleaner make sure to clean the throttle body sensor. By doing this you can prevent the buildup of dirt and ensure smooth operation. 

Note: Avoid using harsh chemicals that could damage the sensor.

  1. Check for Proper Adjustment: Make sure according to manufacturer specifications the Throttle body sensor is properly adjusted.  Incorrect adjustment can lead to erratic behaviour and poor performance. 
  2. Use Quality Parts: Use high quality parts from reputable brands while replacing the throttle body sensor as it ensures reliability and longevity. 
  3. Monitor Performance: Regularly check on your vehicle’s performance and be attentive to any changes in throttle response and engine performance. This can help you to identify potential issues before it becomes a major problem. 


In conclusion, the throttle body sensor is one of the crucial parts of your vehicle that need to be in good condition. Bad throttle body sensors can lead to a car’s overall performance. If you find any bad signs of TPS earlier then make sure to address it soon. In this comprehensive guide you have learnt all the necessary information about TPS.  Have safe driving! 

In case, you’re looking to sell your damaged car in Sydney, NSW then Scraply is the best option for you. They provide hassle-free solutions for scrap, old cars and pay you a top amount in return. 

Hudson James has been with Scraply since 2015. He loves cars and cares about the environment. As a kid, he liked fixing cars with his dad. Later, he saw a car get wrecked and left on the street, which made him think about how to use old cars better. At Scraply, he helps people easily get rid of their old cars and make sure they’re recycled. Hudson believes every old car should have a new life. He’s happy to make the world better, one car at a time.

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