The fuel door is a metal protective cover that helps keep debris out of your fuel or gas tank. It is usually found on the left or right side of the vehicle near the trunk. Over time, the fuel door hinge or spring can corrode. This may cause your fuel door to remain open, exposing your filler cap to debris and moisture that could damage the filler cap. It could also cause the fuel door to get stuck closed, making it difficult to refuel. If you are having issues with your fuel door, check out O'Reilly Auto Parts for the right replacement fuel door for your vehicle.