MY PRIUS IV, PURCHASED NEW IN 2010, INTERMITTENTLY HAD A LUNGING FORWARD PROBLEM WHEN GOING OVER SPEED BUMPS, POT HOLES ETC. I WOULD HAVE TO STOP IT BY BRAKING QUICKLY, SO I DIDN'T COLLIDE WITH A CAR AHEAD. I INFORMED TOYOTA OF THIS PROBLEM WITHIN THE FIRST YEAR. THEY TESTED IT AND SAID THEY COULD FIND NOTHING. I MENTIONED THIS TO THEM ON VARIOUS OCCASIONS WHEN I TOOK THE CAR FOR ITS PERIODIC MAINTENANCE OF 5000 MILE INTERVALS. ON DECEMBER 26, 2012 I WAS STOPPED WAITING TO GO LEFT WHEN I WAS REAR-ENDED. I WENT TO PULL OVER TO THE SIDE OF THE ROAD TO ASSESS THE DAMAGE. WHEN I ACCELERATED TO GET TO THE SIDE OF THE ROAD,THE CAR TOOK OFF CRAZILY, AT A HIGH RATE OF SPEED FOR ABOUT 6-7 SECONDS, ZIGZAGGING UNCONTROLLABLY ON THE 2 LANE ROAD. IF THERE WERE CARS COMING TOWARD ME, I WOULD HAVE BEEN IN A HEAD ON CRASH. I IMMEDIATELY CALLED TOYOTA SERVICE OF SCRANTON,PA AND ASKED THEM TO SEE AND ASSESS THE CAR'S PROBLEM. THEY MADE AN APPOINTMENT AND CONCLUDED.SAID THERE IS NO PROBLEM INTERNALLY, AND SUGGESTED REMOVING THE AFTER MARKET FLOORMAT. I THEN PROCEEDED TO SHOW THEM THE SAME PROBLEMS MANY CUSTOMERS ARE HAVING WITH THE PRIUS , INCLUDING AN ARTICLE BY STEVE WOZNIAK, THE CO-FOUNDER OF APPLE COMPANY, WHO HAD ACCELERATION PROBLEMS WITH HIS 2010 PRIUS. I CALLED THE MAIN TOYOTA HEADQUARTERS LATER, EXPLAINING THE PROBLEM AND THEY TOO SAID THERE IS NO MALFUNCTION , ONLY MENTIONING THE FLOOR MATS AGAIN.. THIS IS NOT THE CASE AS THE CAR HAS HAD ACCELERATION PROBL