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Q: Cruise control turned on, sudden acceleration, high revving

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My car has 74,000 miles on it. Recently, I was driving uphill at speed around 56 mph, when the cruise control was activated and the car started accelerating suddenly by itself. At that point, the engine was revving high and the RPM jumped to over 4000. I started to brake and the cruise control turned off. There was a vibration in the steering wheel as well. Also, upon applying the emergency brake, it suddenly went to the floor and was completely unresonsive. I managed to bring the car to a halt. The dealer couldn't find the problem and said the car requires further inspection. Do you have any idea what happened to my car?

A: Hey there. This could be from a defective c...

Hey there. This could be from a defective cruise control switch shorted or a problem with the throttle control actuator. The vehicle should be towed to the dealer and left there until they verify and repair the problem. The dealer will not repair something unless they can duplicate the problem. Without duplicating the issue it cannot be diagnosed. Check to make sure your floor covers are secure away from the pedal. If you would like to have an outside expert give the car a second opinion, a qualified professional from YourMechanic can come to your car's location to inspect the acceleration, cruise control, and vibration issues.

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