When accelerating from a stop, my car will not go over 20 mph. It just revs up like its not changing gears . I have to pull over and park it. It runs fine afterwards. This ds not happen all the time. Usually it happens once a month. Its been to the dealership 3 times. They drive it around the block and tell us that they cant replicate the problem. Therefore, they dont troubleshoot anything and return the car to me. Im truly scared to drive it. I wrecked twice at a red light intersection.