I don't know if anybody has had this problem before but I had it happen to two of my Mustangs, gas fumes smell through my air vents, I fixed the problem by replacing Vapor Canister Purge Valve, so I thought I would share.
Interesting I have that smell coming through the air vents but only when the car is running rich on a bama tune. No tune and no richness = no smell through air vents for me. Thanks for sharing.