Engine shuts off when opening gas cap, what causes this?

Hello, you're opening the gas cap with the vehicle running? Turn off the engine before you get gas, when you open the gas cap with the engine running, the Purge valve is most likely open at that point and you're causing a huge vacuum leak into the intake manifold. Shutting down the engine will close the Purge valve, open the vent valve and allow for refueling. Thats what the air sound is, its manifold vacuum being drawn into the gas filler pipe. Vehicles are not designed to be refueled when running. You're causing a huge Evap leak.

https://www.2carpros.com/articles/evap-system-code-repair

The purge solenoid could be stuck open remove the valve and try to blow through it to confirm, here is the location in the images below. Let me know what you find.