I got a 2016 mini cooper s. 2 days ago i overfilled the gas tank because the gas pump was malfunction. I noticed the gas pumping was exceptionally slow. I waited and waited inside the car. Then i heard water streaming sound. I went out and check the gas was spilling out. The gas station employee wouldn’t give a damn. Today i feel the engine is very shaky and loud. I am not sure if it’s because of the cold weather. It’s -10F here. Could the engine be damaged? Thanks
Never a good idea. You have probably saturated the overflow charcoal filter and a drive and drying time should clear it up.
1 Like
Although it is not a good practice to overfill, one time should not hurt anything. Some pumps have a replaceable filter on the pump. If that filter gets water or ice in it it may slow the fuel flow to the point where the pump doesn’t sense the fuel flow to shut off the pump.
You are lucky the attendant didn’t care. In most states you are responsible for attending a self service pump. You could have been liable for cleanup costs.
In my part of NY State, most trigger locks have been removed for liability issues.
2 Likes
I agree with oldtimer_11. One time usually doesn’t hurt anything. If your check-engine light comes on soon, then you might have a minor issue with the evaporative emissions control system that could go away on its own.
As already mentioned, you need to keep a closer eye on things when you’re filling up in the future.
Around here there are signs on the pump to stand nearby just for this kind of thing. Pump nozzles don’t always shut off the way they are supposed to and leaking gas all over is a fire hazard. The other thing to check is if the nozzle is shut off before turning the pump on. I learned this the hard way spraying gas all over the car. Doesn’t help the wax much.
I suspect that, possibly combined with overdue maintenance, is responsible for the shaking.
Get all the maintenance up to date, throw some new plugs in it, and enjoy your Mini. It that doesn’t work, move to a warmer climate. 
I am guessing things got boogered by overfilling and many self heal given time.
Appreciate your response.
This morning when i turned on the car, i got a alert sound saying Drivetrains malfunction. I couldn’t start up the car because i couldn’t step on the brake. The brake pedal is like a hard solid rock no matter how hard i press it. Could this overfill cause this problem? Or because some brake fluit or some other oil/fluit is frozen because it’s currently -20℃ or -8℉
Thanks
No, overfilling the gas tank has nothing whatsoever to do with a brake problem.
Given the number of problems that you are currently having with this car, I don’t think that you have any alternative to having it towed to the dealership.
And, given that it is a 2016 model, unless you have racked-up a lot of miles, all of the problems should be covered under warranty. If–as I suspect–the car is still under warranty, don’t screw things up by attempting to fix it yourself, or by having an independent mechanic try to fix the various problems.
Good advice from VDC. Have the dealer tow it back for warranty maintenance.
As is always good practice, be sure to keep your copies of the shop orders.
Over-filling the gas tank wouldn’t normally cause the engine to sputter, at least when you’d driven a while and the tank was back to normal levels. But if you got unlucky, it could. What could make that happen? Liquid gasoline goes into the charcoal canister on an over-fill. It is only designed to hold gas vapors, so the liquid gas could damage it. What worse, the damage to the canister could allow very small particles of charcoal to be ingested, which could clog the fuel injection system.
We can come up with lots of reasons why this is all your fault, but that’s just nonsense. Your car might just be suffering from being very, very cold. It should still be under warranty. Is it?