I WAS DROVE THE CAR FOR SHOPPING 25 MILES AWAY FROM HOME AT 9:00 AM. AT 11:50 AM, ON THE WAY BACK, THE BACK SHOOK SLIGHTLY AND MADE SMALL NOISES THAT WERE UNFAMILIAR. I CHECKED TO SEE IF THE SHIFT GEAR WAS SET CORRECTLY AND WINDOWS WERE CLOSED, WHICH THEY WERE. THERE WAS NO UNUSUAL BLINKING OF DRIVER PANEL LIGHT INDICATING ANY TYPE OF WARNING. WHEN I ARRIVED AT THE DRIVE WAY AT 12:30PM, TURNING INTO THE FRONT OF THE HOUSE AS USUAL, THE CAR SUDDENLY ACCELERATED AND MY CAR RAN INTO THE GARAGE DOOR AND SIDE OF THE HOUSE.