My car has some sort of problem that makes it run on the rough side and be a bit sluggish. I have smelled some gasoline from time to time. One day recently I really could smell the gas so I opened the gas door and opened the gas cap and gas literally gushed out. Today, I could smell a little gas and opend gas door and saw a drop of gasoline dripping from the gas cap.



1. Is it common that a gas tank gets pressurized to the point of gas wanting to come out the gas cap?

2. If no to No. 1, what could cause such a thing to occur?

3. Is my gas cap bad as well?

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1999 Mercedes ML320
2002 Mercedes 230K