Throttle Position Sensor

Learn more about the functioning and the malfunction of the TPS

What does a Throttle Position Sensor do?

The Throttle Position sensor moves with the throttle and sends a voltage signal to the computer indicating throttle angle and speed of movement data. The computer uses this data to measure engine load, adjust timing, fuel delivery, EGR, converter clutch operation and clear flood mode.
The TPS is mounted on the throttle body.
Symptoms of a Defective TPS
One unique thing about TPS failure is that all the symptoms may show up at the same time. It doesn't mean that they show individually, but it often happens that you'll notice more than just one sign.
- The 'Check Engine' Light is On
This is the first thing that you'll notice. The light is meant to tell you, the driver, that something is wrong with either a component of the car, or its sensor. It's always advisable to get your car checked out by a mechanic as early as possible if this light is on.
- Bucking and Jerking/Hesitation while Accelerating
Another common symptom related to a bad TPS is the jerking of the car, especially when accelerating. Without proper inputs from the TPS, the on-board computer is unable to guide the engine to work at optimum levels.
- Idle Surging
This problem usually comes in conjunction with the above one. Similar to getting jerks while accelerating, with a faulty TPS, the computer cannot tell if the throttle is fully shut when the car is idling.
- Sudden Stalling of the Engine
This can happen anytime, without any kind of warning, while driving or idling. The TPS can give a bad input, prompting the engine to stall.
- Sudden Surge in Speed While Driving on the Highway
This is a particularly hazardous situation. What usually happens is that at high speeds, the butterfly valve inside the throttle may close up, and if the driver pushes on the pedal harder, the valve 'pops' open suddenly, giving the car an unintentional burst of speed. All of this happens if the sensor is unable to detect the closed position of the throttle.
How to Check a Throttle Position Sensor ?

Disconnect the TPS connector.There are three wires going to the sensor body, the negative ground, the +12 Volt input, and the variable output to the onboard computer.
Insert the alligator clip test leads into the appropriate jacks on your DMM and set the "Range Switch" to the 20,000-Ohm or the 20K Ohm scale.
Connect one of the test leads to the center connector, the computer output connector, and the other lead to either the +12 volt or the – Ground connector on the TPS connector. The polarity of the test probes doesn't matter when making this test.
3  Slowly, move the throttle through its full range of movement from its "closed" position to its "full open" position, while observing the digital readout on the DMM. It should increase or decrease steadily and evenly as the throttle linkage is moved through its full range. Any sudden drops or increases in the reading indicate a bad TPS, which needs to be replaced. A drop to infinite resistance at any point indicates a break in the TPS's resistance element and also indicates a bad TPS.

If Throttle Sensor is replaced or removed, it is necessary to install in proper position, by following the procedures shown below:
- Install Throttle Sensor body in the Throttle Chamber. Do not tighten bolts. Leave bolts loose.
- Connect Throttle Sensor harness connector.
- Start engine and warm up sufficiently.
- Measure output voltage of Throttle Sensor using voltmeter.
- Adjust by rotating Throttle Sensor body so that the output voltage is 0.45 - 0.55 volts.
- Tighten mounting bolts.
- Disconnect Throttle Sensor harness for a few seconds and then reconnect it.

Do you have a problem on your TPS ?


Decarbonization allows to clean effectively your engine.

Preventive engine cleaning enables you to restore engine parts rather than replacing them, thereby saving vehicle owners on costly parts, such as a new turbocharger (1.350€ - 3.100€), catalytic converter (600€ - 2.000€), DPF (600€ - 2.000€) or EGR valve (370€ - 500€).

These problems result mainly from poor combustion, which stifles the engine.

So before replacing your engine parts, try Carbon Cleaning. A dirty engine as the result of carbon deposits is the new threat to vehicle performance.

Make your online diagnosis
Center Locator
Find the Carbon Cleaning center closest to you
With the Carbon Cleaning solution,
you can help extend the life of your car engine
without the need to replace so many expensive parts.
Locate a center
near you :
Become a distributor-partner of Carbon Cleaning
As a member of the Carbon Cleaning network,
you are an independent vendor. To help you grow
your business, we put all of our experience and expertise
at your disposal.
Contact us with any questions
or for more information about how to become a partner.
Professional Information and Contact
Already have a Carbon Cleaning Pro account? Sign in!
Discover our new machines !!!
Replace the coolant in less than 5...
Thanks to our Flash Cooling stations, the draining, bleeding and replacement of the coolant is carried out in less than 5 minutes. Increase your turnover and save time with these...
Discover our new machines !!!