Fuel is generally “clean” when it leaves the refinery, but when it’s transferred to a truck or sits in a storage tank at a gas station, it can become contaminated with debris. This debris can be transferred into your fuel tank when you fill up your vehicle. The fuel filter helps to prevent these contaminants from clogging your fuel injectors, thus helping to maintain fuel economy and performance. If a fuel filter becomes clogged, it can cause fuel pressure to drop. You may also experience issues with starting your vehicle or have a hard time keeping it running.