My friend's 2019 EX popped the warning message to tighten the fuel cap. She did, but it's still on after a restart. She'll do it again, but any thoughts about what it might be if not the obvious?

 

Sometimes it takes a few miles of driving or on/off cycles for the system to catch up, so to speak.

Outside chance there is something wrong with your evaporative canister, but I'd wait to see if the fuel cap warning resets on its own.

 

Seconding the first of what bargainguy said and adding to his second statement. Fuel cap off could be fuel pressure sensor as well. In an off chance that your purge valve is stuck open but the voltage variance to the computer is within spec and not causing a code, that could be a problem as well. Clear the code and see how soon it takes to come on. If it's after shut down/overnight for a solid 7 hours, I'd go with EVAP/purge related. Smoke test and test components with bi-directional scanner. If it pops up immediately or you can see the fuel pressure sensor read out and it's stuck at something obtuse, test the FPS and go from there. Good luck!

 

Out of curiosity, did the owner have a habit of overfilling (continuing to fill, possibly repeatedly, after the pump clicks off the first time)?
That's the sort of behavior that can cause evap system problems.

 

I'll ask her about overfilling tomorrow when we get together for our traditional Wednesday cocktail hour(s).

In fact I suspect it may have resolved itself (because I haven't heard more), and thank you all for your input, which I shared with her. It's under warranty, so it would go to Honda if it's persisting.

 

Like mentioned above it could mess with Evap from overfilling. That can oversoak the Charcoal filter. I have issues in my Lexus in past with previous owner, so just ringing out thoughts as well.

 

Thanks everyone. I've loved this forum since before my GK existed.

The light took a day, but went off. All is well with my friend's Fit.

As usual, the cocktails were lovely too.