Spray formulated for all diesel engines with any fuel system, it cleans the ducts, the intake valves and the EGR unit. The EGR valve featured in diesel engines serves the purpose of recycling a certain amount of exhaust in the cylinder. Part of the fresh air intake is therefore replaced with exhaust fumes, with the aim of lowering the temperature during combustion with a subsequent drop in nitrogen oxide. By recycling exhaust fumes, the valve is subject to contamination and poor operation. The EGR valve spray cleaner is specifically formulated for cleaning the "EGR unit", and also cleans intake ducts and valves.