my 2014 tioga 25g ford chassis...check engine light massive evap leak..continued driving and additional light for gas cap...took it to ford dealer...moved clamps around on fuel filler hose between tank and fuel filler...reset lights..smoke test..250 dollars paid by fleetwood...drove 300 miles and lights back on...got under r.v. and looked and all looked good..read there is a leak somewhere..so I put additional clamps at each end of fuel hose reset codes...no problems so far 1500 miles..keeping my fingers crossed..that was back in march of this year.