PARKED IN PARKING GARAGE. WHEN BACKING UP, CAR LURCHED AND RAN INTO ANOTHER VEHICLE THAT WAS BACKING UP. I WAS IN REVERSE WHEN THE OTHER CAR BACKED UP. FOOT ON BRAKE AND CAR LURCHED INTO OTHER CAR. NO PERSONAL INJURIES THAN GOODNESS. *TR SINCE THAT TIME, IT HAS LURCHED IN BOTH FORWARD AND REVERSE. I ORIGINALLY THOUGHT THAT SOMEHOW MY FOOT HIT THE GAS PEDAL AND COULD NOT FIGURE OUT HOW I WAS DOING THIS. I ALSO THOUGHT THAT MAYBE THE FLOOR MAT HAD SOMEHOW BOUND THE GAS PEDAL, BUT, I CHECKED AND IT IS NOT THE PROBLEM. SENSOR REPLACED ON CAR AS MECHANIC THOUGHT THAT THIS MIGHT BE CAUSING THE PROBLEM. IT WAS FINE AFTER THAT FOR ABOUT 1,500 MILES AND PROBLEM HAS STARTED AGAIN. THE PROBLEM SEEMS TO BE MADE WORSE IF THE TEMPERATURE IS OVER 90 OUTSIDE OR IF THE CAR IS SITTING AND IDLING OR OPERATING AT LOW SPEEDS. I HAVE BEEN LUCKY THAT NO OTHER PROPERTY DAMAGE AND/OR PERSONAL INJURIES.