Valves have all kinds of applications. They are major components of automotive design. Valves are used in many different ways in a car. They generally provided some kind of open/close action. They allow currents, fluids, air, fuel, and signals to flow at appropriate times. Valves that malfunction can mean the destruction of an engine or simply an inconvenient. Valves may require immediate attention or can be put off until time and money permits their repair. But most of the time, valves are parts of necessary systems. They can be messy to replace in some instances and require professional mechanics. In other cases, they are easily accessed and easily replaced even by amateurs. Valves are used in the fuel injection system, air intake, brake systems, oil system, coolant system, etc. They are just about everywhere. They are age old technology that even the most advanced of vehicles cannot do without.