The start-up is a transient state of operation of an internal combustion engine during which many negative phenomena occur that affect the technical condition of the engine, its electrical equipment and the natural environment. The start-up process of an internal combustion engine is influenced by many factors, such as: technical condition of the starting system, technical condition of the engine, battery charge level, lubricant properties, engine standstill time, engine temperature, etc. Mechanical energy is required to start the engine, supplied by an electric starter by drives the engine’s crankshaft. Knowledge about the operating parameters of the electric starter during the start-up process is important not only for the user of the engine (vehicle driver), but above all for designers of modern combustion engine starting systems and service personnel. The paper presents the results of experimental tests of electrical parameters of the single-cylinder diesel engine start-up process at variable fuel injection parameters under ambient temperature conditions.