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Q: My car revs it's rpms when at park and drives itself to 25 mph without pressure on the gas pedal

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So when I start my car up it spits and struggles to come alive, when I put it in park the car wants to rev up the engine and rpms, and when the car is in drive it drives itself slowly upto 25 mph without any pressure on the gas pedal. What could be the problem with that?

My car has 240000 miles.
My car has an automatic transmission.

This may be a sign of a failing throttle position sensor. The throttle position sensor (TPS) is a sensor used to monitor the throttle position of the throttle plate inside the throttle body in relation to your foot position on the gas pedal. The sensor is usually located on the throttle plate so that it can directly monitor the position of the throttle. The ECU then makes the direction to supply more or less fuel to the motor. When this sensor is not working properly, this can cause intermittent responses when pressing the gas pedal. I would suggest having a professional from YourMechanic come to your home to diagnose your throttle control system.

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