VEHICLE HAS TWICE ACCELERATED FORWARD UPON BRAKING WHEN COMING TO A STOP. FIRST TIME WAS IN A PARKING LOT. VEHICLE WAS PULLING INTO PARKING SPACE, SLOWED TO A CRAWL WITH THE BRAKES APPLIED, THEN SUDDENLY LUNGED FORWARD, HITTING THE CAR PARKED DIRECTLY IN FRONT OF VEHICLE. NO DAMAGE OCCURRED, BUT EXPERIENCE VERY FRIGHTENING. SECOND TIME WAS RETURNING FROM DOCTOR APPOINTMENT. A PASSENGER IN THE VEHICLE AT THE TIME AND EXPERIENCED THE DEFECT. WHILE COMING TO A STOP BEHIND A GROUP OF CARS AT THE STOP LIGHT, BRAKES APPLIED TO SLOW THE CAR TO A CRAWL, THEN SUDDENLY THE CAR SURGES FORWARD. UPON SLAMMING BRAKE FULLY TO THE FLOOR, THE VEHICLE STOPPED, MISSING HITTING THE CAR AHEAD AND STOPPED BY ONLY INCHES. VEHICLE WAS TAKEN TO DEALERSHIP, WHICH KEPT THE CAR OVER THE WEEKEND, SUPPLYING A LOANER CAR. CALLED DEALERSHIP MONDAY AFTERNOON. TOLD THERE WAS NOTHING WRONG WITH THE VEHICLE. IT WAS DRIVEN A TOTAL OF 80 MILES OVER THE WEEKEND AND THE PROBLEM WAS NOT RECREATED. THE TROUBLE IS, IT WAS ALMOST 450 MILES BETWEEN THE FIRST PROBLEM OCCURRENCE AND THE SECOND ONE. THEY WERE ALMOST ONE WEEK APART. NOW I AM TOLD BY THE DEALERSHIP THAT SINCE THE COMPUTER FOUND NO DEFECTS OVER THE WEEKEND, MY CAR IS READY FOR ME TO DRIVE. I NOW HAVE A DEFECTIVE CAR WITH A SERIOUS SAFETY ISSUE, WHICH I AM AFRAID TO DRIVE. I TOLD THEM I WANTED A PIECE OF PAPER STATING THE CAR WAS FREE OF DEFECTS, SO WHEN THIS OCCURS AGAIN, I WILL BE NOTIFYING MY INSURANCE COMPANY AND WE WILL TAKE ACTION AGAIN