Abstract <p>The modeling of discharges in pulsed plasma ignition systems is considered; the nonlinearity of the spark discharges in spark plugs is taken into account. The following output parameters are expressed as a function of the discharge processes: the energy and duration of the spark discharge, the discharge current, and the ignition capacity. Cases with and without synchronization of the discharge processes in high-voltage and low-voltage storage capacitors are analyzed. The formulas obtained may be used to assess the efficiency of the ignition system in a real engine, without the need for direct measurements, which, as is well known, may disrupt the gas dynamic processes in the combustion chambers.</p>