2009 Toyota 4Runner Fuel System

DRIVING ALONG A TWO LANE U.S. HIGHWAY AT THE POSTED SPEED, I NOTICED THAT MY FUEL GAUGE WAS SHOWING FULLY EMPTY, AND THE WARNING LIGHT WAS FLASHING. PUSHING THE ODOMETER TRIP BUTTON, I NOTICED THAT I HAD NOT YET REACHED THE MILEAGE FOR A "NORMAL" FILL UP, WHERE I ROUTINELY GET 20-21 MPG. AT THE END OF THAT TRIP,WHEN I TURNED THE VEHICLE OFF AND RESTARTED IT, THE FUEL GAUGE SHOWED HALF FULL. USING THE TRIP ODOMETER, I DROVE AN ADDITIONAL ESTIMATED 30 MILES TO HOME. THE FUEL GAUGE CONTINUED TO DISPLAY HALF FULL. THE NEXT MORNING, I DROVE APPROXIMATELY 3 MILES TO THE GAS STATION, AND WAS SURPRISED WHEN IT TOOK ALMOST 15 GALLONS TO FILL THE TANK. THE NEEDLE ON THE GAUGE THEN WENT TO FULL. SINCE THEN IT HAS ONLY COME DOWN TO ONE HALF, YET MY MILEAGE NOW IS AT THE POINT (261-270) WHERE I NORMALLY FILL UP WHEN THE NEEDLE NEAR THE EMPTY LINE. I BELIEVE THIS PROBLEM IS NO DOUBT WIDESPREAD. *TR