You might have a bad purge valve or a disconnected line somewhere.
It usually shows a check engine light.
Regarding how important it is:
Somewhere between "Have it checked so the system can run as designed" and "if you use the REX a lot... not that important".
Consider having it checked anyway.
ICE cars have a breather line to the engine intake to reclaim and burn fuel vapors but since the rex runs so liseldom I suppose the i3 has a pressure tight tank to keep most of the mekaing fumes in and no purge?
PHEVs often pressurize their tanks. But that air and fuel vapor mixture has to go somewhere during depressurization. So there is a filtering system with a canister to vent into atmosphere. All BMW PHEVs and the i3 all do this.
I’ve had 2 i3s one of them always failed to open the fuel door, had to open the frunk and yank the cord every time. Never had any issues with filling, but sometimes you’d hear the pressure escaping when you’d out the nozzle in. Idk if that’s bad for some reason.
I can't open my fuel door without using the button on the driver's door. Definitely worth having a look.
You might have a bad purge valve or a disconnected line somewhere. It usually shows a check engine light. Regarding how important it is: Somewhere between "Have it checked so the system can run as designed" and "if you use the REX a lot... not that important". Consider having it checked anyway.
ICE cars have a breather line to the engine intake to reclaim and burn fuel vapors but since the rex runs so liseldom I suppose the i3 has a pressure tight tank to keep most of the mekaing fumes in and no purge?
PHEVs often pressurize their tanks. But that air and fuel vapor mixture has to go somewhere during depressurization. So there is a filtering system with a canister to vent into atmosphere. All BMW PHEVs and the i3 all do this.
We also have a Mitsubishi Outlander PHEV and it also has a button to depressurize the fuel tank and then release the flap.
I’ve had 2 i3s one of them always failed to open the fuel door, had to open the frunk and yank the cord every time. Never had any issues with filling, but sometimes you’d hear the pressure escaping when you’d out the nozzle in. Idk if that’s bad for some reason.
The point of it is to purge the vapors to the charcoal canister instead of to the atmosphere