Its definetly the fuel boiling as it has happened to a number of cars around here and I saw the fuel boiling out the vents. When it happens you have to hold the pedal on the floor to start it just like starting a flooded vehicle. Never had this problem until last year. Its the pump gas fuel they have around here. It would be cool if I can figure out how to keep the under hood temps down. I really did not want to rap my headers but it may help as suggested. Ron