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Q: What's going on when gas is constantly slowly leaking from where the gas cap is and the cap was not under pressure when opening?

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I filled my car up with gas yesterday evening and when I got home I smelled gas. I didn't drive this car today. I noticed gas just dripping from where my gas top is. I took cap off and gas is literally at the hole just sitting and dripping. What's wrong?

My car has 96656 miles.
My car has an automatic transmission.

A: It is possible the tank was filled too much...

It is possible the tank was filled too much, that is the gas pump did not shut down when it should. Even if gasoline was not filled right to the top, thermal expansion can later cause the gas to overflow if the tank gets warmer and pressure builds. The too high level will subside quickly as all you have to do is drive 25 miles or so to lose a gallon. If you believe there is a leak or other issue, a certified Mechanic from YourMechanic can perform a leak inspection during a mobile visit.

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