Opening your BMW 4 Series gas tank is as easy as pushing down on the fuel-filler door. But before you do it, make sure that your vehicle is in park, the engine is off, and the doors are unlocked. Otherwise, the fuel-filler door might not open.

Whether you drive a 430i or an M4, most BMW gas tanks are designed to open at a push on the fuel-filler door. But it won’t work unless the vehicle is stopped and the doors are unlocked. Not only does this allow for safe fueling, but it also prevents anyone else from tampering with the tank or taking your fuel.

If you’ve followed the advice above but still can’t seem to get your fuel-filler door open, there could be an underlying issue with the latch itself. If that’s the case, it’s typically best to bring your car to a mechanic or BMW dealership that can help. Your owner’s manual may have instructions on how to manually release the fuel-filler door latch, although the process could look different depending on the model you drive.

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