The fuel guage on my 3520 is acting strange. It is new, <30 hrs. Yesterday after it had been parked for a while, I fired it up to put it away. As I pulled into the garage the fuel light began rapidly blinking and the guage dropped to E. I turned it off and back on and it stayed on E and the light kept flashing. There is well over half a tank of fuel and no signs of a leak. Any ideas?