The study evaluates current periodicity of engine air filter replacement to determine influence of this operation on some vehicle performance parameters. Experience of usage, costs of exploitation and technical condition of vehicle are connected with technically and economically based system of technical servicing. Periodicity of motor air filter replacement, declared by automobile manufacturer Renault ranges from 30 000km to 120 000 km, depending on model and engine type. According to the same recommendations, periodicity must be reduced by a half, if conditions of use include dusty roads and exploitation of vehicle in the urban conditions. Aim of research is to evaluate criteria, according to which actual replacement of motor air filters was performed and to measure influence of air filters with different levels of use on the engine performance. To reach the goal, air filter elements from 90 vehicles, which are used in Latvia were collected. Influence of air filter clogging on several vehicle exploitation parameters, such as engine power and fuel consumption was analyzed. Value of maximum permissible pressure difference before and after air filter was determined. Air filters, collected from vehicles, were tested on chassis dynamometer for value of air pressure difference. Results obtained with all the samples have been presented and critically examined.