It's p1456. Replaced the fuel cap with an oem from the dealer. The code came and went. I pulled the fuse for the ecm and left it 10 secs then replaced. That was about 12 days ago and almost 2 tanks of fuel. I still have some fumes but not as much. I haven't seen any wet spots or leaks anywhere. I'm using less fuel now too.

 

The system relies on the fuel tank being airtight. It might be (guessing) that along with (or because of) the leaking cap, your EVAP canister got saturated with liquid fuel instead of just taking vapor.

New fuel cap fixed the error code. Time & use gradually cleared out the EVAP canister.

Using less fuel is good too.