 It sounds like the same problem that some new Ford Explorers have experienced.  But, that problem is a vent design flaw that the F150 doesn't have. The dealer,  of course,  can't duplicate it.  My daughter and I nearly choked to death. It happens on the freeway, or under heavy acceleration.  There's also a raw gasoline smell when exiting the freeway on a long offramp deceleration.  Electrical dash problems come and go. Driver window auto up, sometimes goes up and down a few times when pressed. Auto stop works about half the time.  Dealer can't duplicate, so can't repair.