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Q: Car revs and accelerates without the gas pedal being pressed

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As I was driving my car down the street, I noticed that it began to feel weird after about three minutes into the drive. While stopped, with my foot on the brake, I could hear the car engine revving as if I was trying to accelerate the car. It happens at 2 second intervals in between. With my foot off the brake, the car starts to accelerate itself to 20 mph in a fashion similar to using cruise control going uphill.

My car has 172600 miles.
My car has an automatic transmission.

This is a common problem when the idle air control module is not functioning as it should. This is a component that helps to monitor air/fuel mixture at idle speed. When this is not working properly, this causes an imbalance in the air/fuel mixture resulting in intermittent or abnormal idling as you’ve described. This could be a known problem by the manufacturer so you may want to contact the dealer to see if this is anything that is covered. If you would rather not get in touch with the dealer, I would recommend having an expert from YourMechanic come to your home to diagnose the revving concern and proceed with proper repairs.

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