BACKED CAR OUT OF GARAGE ONTO DRIVEWAY. PASSENGER SIDE MIRROW WAS NOT IN PROPER POSITION. PUT VEHICLE IN PARK AND LEFT ENGINE RUNNING. WALKED AROUND CAR AND WHEN I TOUCHED MIRROR VEHICLE STARTED MOVING FORWARD. JUMPED IN PASSENGER DOOR AND LEANING ACROSS CONSOLE PUT HAND ON BRAKE. BOTH DOORS SLAMMED SHUT AND WERE DAMAGED AS DOORS HIT GARAGE FRAME.REACHED UP WITH OTHER HAND AND SHUT ENGINE OFF. A FEW YEARS AGO I HAD AN ISSUE WHERE THE CAR WAS STOPPED AT A LIGHT AND WHEN I TOOK FOOT OFF BRAKE AND TOUCHED THE GAS THE CAR WOULD NOT MOVE. THIS WAS A SOFTWARE ISSUE AND DEALER HAD TO REPROGRAM SO IT DID NOT HAPPEN AGAIN. THIS SEEMS TO BE THE REVERSE WHERE THE ENGINE WAS IN PARK BUT STARTED MOVING FORWARD ON ITS OWN. DRIVEWAY SLOPES DOWN FROM THE GARAGE TO THE STREET.