Composition for precise control of spray flame, performance, and airtightness of gasoline engine fuel injectors during testing on special diagnostic stands. • Provides an accurate assessment of the actual condition of fuel injectors • Has standard density and viscosity parameters that comply with GOST/State Standard of Russian Federation R 51866-2002 • Suitable for injectors of all types: euro, asia, usa, including those with increased pressure and high opening frequency • Maintains constant viscosity for correct diagnostic procedures • Safe for injectors, rubber seals, and diagnostic equipment • Contains a viscosity corrector • Non-toxic, with no pronounced odor, difficult to ignite • Does not mix with cleaners, does not evaporate, and maintains functional properties for a long time.