Some gases exhalation whenever I open the fuel cap!!!

[Ryan Heo]

Hi.Whenever I open the fuel cap to filled up in a gas station, some gas is exhaled. I know it is gasoline, I don't know why. The other cars of my family are ok. Only my car make to give off gas which is not gasoline.Something Wrong is it?Thanks.

[rxm6]

No thats normal...thats your evap system working perfectly. What it does is it preserves gas fumes from either the evap canister or gas heating up on a hot day and it pressurizes your system to give you better fuel economy.

[Ryan Heo]

Thank you to let me know that.I thought it has some problem.Thanks.