How to Reset a Throttle Position Sensor

How to Reset a Throttle Position Sensor
There are times when it is necessary to reset a throttle position sensor (TPS). Maybe the sensor is getting replaced with a new unit or the old unit was removed to service the throttle body. It is also possibly a case where the onboard engine computer lost track of the throttle position with time. Or maybe throttle response just isn’t as “snappy” as it was at one time. Luckily, resetting a throttle position sensor is fairly straightforward. Here’s how to reset your TPS when the time comes.
What is a Throttle Position Sensor?
Back in the old days of non-electronic carbureted engines, the only throttle position sensor was your right foot. Push a little, go slow, push a lot, go fast. Now it’s up to a computer to decide how much fuel to squirt into the engine, and that means knowing what the driver wants. That’s where the throttle position sensor comes into play.
This sensor is typically attached to the throttle blade shaft (inside the throttle body) where it can directly measure how far open the throttle blade is at any time. Different automotive manufacturers use different sensor designs and onboard computer software to operate. Most modern vehicles have moved to a “drive-by-wire” throttle input system where the gas pedal is not physically connected to the throttle body.
The gas pedal itself is a sensor telling the throttle body blade motor how far to open. The throttle position sensor works in conjunction with the throttle body motor to make sure things are in sync. Regardless of how the throttle position sensor operates, it sends back important information to the onboard computer to help control precise fuel delivery to the engine.
Resetting a Throttle Position Sensor
There is no “one size fits all” method to reset a throttle position sensor. Years ago, resetting a TPS involved using a multimeter to read the sensor output while loosening the sensor itself and turning it slightly on its mounting pad to reach a certain output value. Most modern methods involve turning the ignition key off and on while pushing the gas pedal to the floor in a certain sequence. Others require specific diagnostic equipment to interface with the onboard computer.
Some of these techniques are technically a throttle recalibration, but many people refer to it as a throttle position sensor reset anyway. While it is not possible to list out every throttle position sensor reset procedure, we can show you a few examples. Here’s how to reset the throttle sensor on two popular vehicle ranges:
Ford Throttle Position Sensor Reset Procedure
Ford vehicles with an electronic throttle body (drive-by-wire) can reset the throttle position by doing the following:
- Isolate the negative battery cable terminal from the negative battery post using a towel or piece of cardboard. You MUST keep the negative battery terminal from touching the negative battery post. This is important as it will prevent the car battery from shorting out during the next step.
- Use a jumper wire to connect the negative battery terminal to the positive battery terminal. Normally, this is a very BAD idea, but in this case the negative battery post is not included in the wiring circuit, thus preventing a short circuit. What this does is drain the capacitors in the onboard computer, wiping away the stored throttle sensor values.
- Remove the jumper wire after two minutes (remove the positive battery terminal jumper wire connection first, then negative battery cable terminal).
- Reconnect the negative battery terminal.
- Turn off all accessories.
- Turn the key to the “ON” position, but do not start the vehicle yet. Wait for the initial dash warning lights to turn off.
- Once the initial dash warning lights turn off, start the vehicle.
- Let the vehicle idle for 15 minutes. Do not touch the gas pedal during this time.
Nissan Throttle Position Sensor Reset Procedure
This procedure should work for 2002–2009 Nissan and Infiniti vehicles:
- Disconnect the negative battery terminal and wait one minute.
- Reconnect the negative battery terminal.
- Start the engine and let it idle until it reaches operating temperature.
- Turn off all accessories.
- Turn the steering wheel to the middle so that the front wheels are pointed straight.
- Turn off the engine.
- Turn the key to “ON” for two seconds and “OFF” again for 10 seconds. Repeat again, leaving the key in the “OFF” position.
- Turn the key to “ON,” but do not start the vehicle. Do not touch the gas pedal yet.
- Wait three seconds and then press the gas pedal firmly to the floor five times in a row, completely releasing the pedal each time. This must happen within five seconds.
- Wait seven seconds.
- Press and hold the gas pedal to the floor for 20 seconds. The CEL will flash and then stay illuminated. Once the CEL stays on (not flashing), within three seconds release the gas pedal.
- Start the engine and allow it to idle for 30 seconds. Do not touch the gas pedal.
Bad Throttle Position Sensor Symptoms
Symptoms of a bad throttle position sensor in your car, truck or SUV include sluggishness, shaking, stalling, bad gas mileage and an illuminated check engine light. If a reset or recalibration doesn’t fix the problems, then it is potentially time for a TPS replacement. Just head to your local NAPA Auto Parts store or shop NAPAonline for your new throttle position sensor. Participating NAPA Auto Parts stores also offer a convenient Buy Online, Pickup in Store option so you can save time. Or you can check out our Free One-Day Shipping on more than 160,000 items.
Don’t feel like DIYing your throttle position sensor or don’t have time? Simply let the experts at one of our 17,000 NAPA Auto Care locations tackle the job for you. Our ASE-certified technicians have the knowledge and right tools to diagnose and repair your throttle woes.
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Brian Medford View All
With an automotive writing career spanning over two decades, Brian has a passion for sharing the automotive lifestyle. An avid DIYer he can usually be found working on one of his many project cars. His current collection includes a 1969 Olds Delta 88 convertible and a slant-6 powered 1975 Plymouth Duster.