Deposits in a general sense are an inevitable consequence of the processes of mixture formation and combustion in the engine cylinder, complex physical and chemical processes with hydrocarbon “participants” in this process—fuel and oil. Moreover, certain qualitative characteristics of fuels, for example, group composition, presence or absence of detergent additives, can have a significant impact on the amount of deposits. Scientific and methodological support for testing fuels for their tendency to form deposits is also important. The complex of works carried out at NAMI Russian State Scientific Research Center resulted in creation of a series of test methods for automotive fuels, which are analogs or equivalents of the generally accepted CEC and ASTM methods, but at the same time devoid of the disadvantages associated with the use of these methods. Comparative tests showed good convergence of results with the analogs. At the same time, all logistical support for testing both gasoline and diesel fuels is carried out on a domestic basis using Russian engines. In the period of general confusion in the European engine industry, uncertainty in the prospects of the automotive industry as a whole, the creation of an independent service for certification testing of fuels for the Russian market and the development of our own methods for assessing the tendency of fuels to deposits using our own engines become an important both scientific and practical tasks.