Originally Posted by skyking
In the gas filler tube there is a line out to a recovery tank for vapors in the fuel tank. I notice lots of people "topping" thier tanks to try to get as much fuel into the tank as they can. This now allows liquid fuel to head to the vapor recovery tank which clogs and fills this tank with gasoline insted of fumes. This in addition to a loose fuel cap may be the problem for this code.
Right on the Money Skyking......This is more than likely the issue in most cases.