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Q: Engine starts to rev up on its own

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The other day I was going to pick up my morning coffee about a mile and a half up hill than down hill. As I was coasting down the hill my engine started to rev like I was trying to downshift but I had my foot lightly on brakes. Scared the you know what out of me, and only stopped when I got to about 15 mph. Went out the next morning and very same thing at the exact same spot so this time I had traffic behind me and could not slow down to 15 and inadvertently as I was going to tap brakes I hit the accelorator for a second and it stopped revving. But it started to do it again after a few seconds and now I'm on flat straight away speed 45 appx. I checked transmission level, color, smell everything looked about right no obvious signs of abnormal or dire need to change immediately but I will just to see if that helps. Brought it to ford today to see if the truck employed the use of engine break and they told me no, and if it just started doing this than its not something normal. What could

My car has 162470 miles.
My car has an automatic transmission.

You may be having a problem with the throttle position sensor or throttle pedal sensor. Have the system scanned to see if any problems or codes are for the throttle position. Also, make sure the floor mat or carpet is not catching onto the pedal. If you’d like a new pair of eyes on the issue, consider YourMechanic, as a certified technician can diagnose any trouble codes that come up and help you fix the problem accordingly.

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