I need help understanding my problem. Have had suggestions before but limited skills and lack of time have kept me from getting it fixed yet. AC recharge seemed to be when problem started. But... If I do NOT run the AC unit and drive it with VENT open there seems to be no smell. When I run the AC the smell appears. Since the AC system is supposed to be(I think) a closed underpressure system why would I get a gas smell ONLY when the AC is running? Starting /stopping it gets a bit worse. Baffled here but that's nothing new

 

Sorry forgot...1996 XLT.

 

If it's really gasoline fumes, you have a leakage in the fuel system, not in the AC system. It's possible that activation of the evaporative canister purge occurs when the AC comes on. That line is known to be fragile as it's one of the few stiff rubber/plastic lines in the system.

Otherwise, the canister itself may be leaking.

On mine, I had a rubber elbow coming off of the canister that deteriorated. Then the little elbow that connects that stiff rubber line to the throttle body was loose. In either case, fumes that were supposed to be sucked into the engine were floating around in the engine compartment and got sucked into the ventilation system through the cracked gasket around the stove pipe of the interior air intake.