Q: 03 Nissan Altima wouldn't accelerate over 50 mph.

asked by on March 25, 2017

I bought a car at a auction so i was getting on the freeway and it wouldn't accelerate

My car has 178459 miles.
My car has an automatic transmission.

Hi there. This sounds like the gas pedal position sensor or the throttle body position sensor is not working properly. You can try manually resetting the gas pedal position sensor. To do this, perform the following:

  • Turn on the ignition key to the ’ON’ position
  • Step on the gas pedal to the floor slowly
  • While holding on the gas pedal, turn the ignition key to the ’OFF’ position
  • Then turn the ignition key to the ’ON’ position
  • Slowly let up the gas pedal to the rest position
  • Then turn the ignition key to the ’OFF’ position

Now you can start the car and go for a test drive. If the symptoms are the same, then I recommend replacing the throttle pedal position sensor and performing another test. If you need further assistance with your car not accelerating past 50 mph, then seek out a professional, such as one from Your Mechanic, to help you.

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