How To Tell Your Throttle Position Sensor Isn’t Working

If you aren’t familiar with the throttle position sensor, it’s responsible for providing your vehicle’s computer with information needed to deliver the right mixture of fuel and air to the engine for each combustion cycle.

The sensor’s regularly updated stream of sensor data allows the computer to calibrate that mixture on the fly, so you have an efficient blend of air and fuel at all times. This makes it important to your vehicle’s proper function. As a result, it’s a part with obvious symptoms when it malfunctions.

Symptoms Of A Bad Throttle Position Sensor

Here are the most common issues seen as the TPS malfunctions. Depending on exactly how it is failing, you may see a few variations on each common theme.

• Acceleration issues including lack of power, lack of ability to accelerate, or random self-acceleration
• Stalling or slower idle are common, as is inconsistent idling that doesn’t match the car’s usual cycle of higher and lower engine speeds
• The car plateaus at a relatively low speed, and in automatic transmission vehicles this often prevents a shift up to a higher gear
• The check engine light comes on while experiencing any other symptom on this list

When you experience these symptoms, it’s time to start checking your favorite automotive supply stores for any specials or deals you can find on a throttle position sensor for sale.

Can You Replace A Throttle Position Sensor Yourself?

It’s actually pretty easy to make this replacement yourself, even with limited automotive maintenance experience. The TPS is typically located on top of the throttle body, which is at the top of your vehicle’s engine. As a result, it is almost always in an easily accessible place. Here’s the step by step for removal and replacement:

1. Locate the sensor on the top of the throttle body by looking for its electrical connector
2. Disconnect your negative battery terminal to power down the vehicle entirely
3. Unplug the electrical connector from the back of the TPS by pushing down its tab and sliding it off
4. Remove the mounting screws from either side of the sensor
5. Remove the sensor from its place
6. Place the new sensor in position and thread the mounting screws by hand
7. Tighten the mounting screws with tools
8. Plug the electrical connector into the back
9. Reconnect the battery terminal
10. Start your car and try accelerating to verify symptoms have ceased

Some vehicles do require position adjustment after installation, in which case you will need to loosen the mounting screws and reposition the sensor until a voltmeter gives you the desired reading. If this is required, details about the operation and voltmeter readings you’re seeking will be in your factory owner’s manual.

Investing in Vehicle Repair Handbooks

Owner’s manuals are designed to help you maintain a car, but they assume a mechanic will do most of the service work. If you’re looking to become a DIY expert in your vehicle’s repair and maintenance, you’ll want to invest in a full repair handbook for your make, model, and year. Luckily, you can find them at practically any store with services like free VIN lookup. Check for yourself.