Diesel filters serve a vital function in today's modern tight-tolerance engine systems. Unfiltered diesel may contain several kinds of contamination. Fuel filters also improve performance, as the fewer contaminants present in the fuel, the more efficiently it can be burnt. The primary purpose of a diesel fuel filter is to protect the fuel system components of the engine. A diesel/fuel filter must be designed to remove extremely small particles to prevent the premature failure of these components, and it is vital that filters need to be maintained and changed at regular intervals.