I was driving on a two lane highway and went to pass a semi-truck that was traveling 10 mph below the speed limit. I accelerated to full throttle (wide open throttle) and as I went into the opposite lane I changed my mind and let go out of gas pedal; however, the car continued to accelerate. I pushed the brake as hard as I could and got back behind the semi. After about 4-5 seconds the car quit trying to accelerate and acted normal the rest of the trip. Asked the dealer about the issue and he stated that nothing is wrong with the car and did not make a note on my paperwork.