Resolved P0457 with intermittent fuel odor in cabin

Driving home on the highway, had the CEL come on. Had noticed a slight fuel odor during the ride. Stopped and picked up my son, we both smelled fuel at another point on the way home (while in motion). Scanned the codes, came up P0457 EVAP System Leak Detected (fuel cap loose/off) as the only code. Gas cap is original, also have noticed that the fuel filler flap spring is pretty loose so the flap is not really flapping.

Is there something else to check in the system (hoses, connections), I assume the fuel filler neck and gasket itself? Seemed like the fuel odor from the gas cap would have blown behind us, but we definitely got a whiff.

Thanks,
Jim

After some more inspection:

- Gas cap was on reasonably tight. I took it off and cleaned it a bit, reinstalled.
- A sticky foam gasket on the inside of the filler neck is not laying exactly correct. I've only ever touched that to replace the fuel pump back in 2017, so it's been like that a while if that is an issue.
- Have not located a source of the fuel smell, but can smell around the parts you'd expect.
- Have not looked at the Vapor Canister, Purge Valve, or Vent valve. Any thoughts on those?

I fixed the foam gasket and replaced the gas cap with a new Motorcraft from RockAuto. CEL went out on a short drive to the grocery store. Still scratching my head on why the whiff of fuel, but guess I'll chalk it up to a leaky gas cap for now.