Modern fuels attack the metal parts of the fuel supply systems. This problem applies especially to older vehicles, because in modern cars, for good reasons, more and more plastic tanks are used. The second problem relates to biogenic fuels and mixed fuels. This problem applies to owners of all ages of cars and modern cars too. In modern fuels bacteria grow in unprecedented quantities. This produces a lot of dirt, especially when the vehicle is not in regular use. The pipes gradually get blocked and the tank becomes contaminated with dirt. Rather than the drastic measure of replacing the entire fuel supply system, regular use of Bactofin will reduce the problem considerably. For vehicles which normally operate with lead-replacement or top oil, using Bactofin is just as easy and will give owners peace of mind. Bactofin also prevents any corrosion of the fuel system. Rust is completely inhibited!