The paper presents issues concerning control of operation parameters of a high-pressure injection system of diesel engines used in farm tractors. Skilful modification of this control by means of electronics brings a considerable improvement of all exploitation characteristics of a tractor. However, success of adaptation depends on the producer’s professionalism and the class of measuring apparatus. It seems that such activities fill in a considerable gap on the farm tractors market and may constitute complementation of the factory offer of the producers of engines for utility vehicles. Successful modifications which have been carried out so far prove that modern diesel engines have high power and rotational moment reserves. It must be emphasised that it influences ecological parameters of the engine.