FIELD: manufacture of engines. SUBSTANCE: method and device for diagnostics of misfire in cylinders of internal combustion engine ensure high reliability of results. Device for diagnostics of misfire may be used both as a component of engine and as independent diagnostics system, for example at service stations. Method consists in recording electrical signal in high-voltage circuit of ignition system in case of break-down between electrodes of spark-plug. Series of diagnostics pulses at magnitude of voltage sufficient for break-down between spark-plug electrodes is furnished to spark plug of cylinder to be subjected to diagnostics in course of discharge of working mixture (fuel-and-air mixture or combustion products) in case preceding to this ignition stroke in cylinder or absence of break-down in case preceding to misfire in cylinder. Presence or absence of of electrical signal in high-voltage circuit of spark-plug is recorded. Absence of electrical signal is indicative of misfire in this cylinder. EFFECT: enhanced efficiency. 5 cl, 4 dwg
