Misfire detection method for a piston combustion engine with electromagnetic fuel charge valve

In piston combustion engines having cylinder valves with completely-variable control and actuation via an electronic engine control, it is also possible to effect a load-dependent control of the piston combustion engine: Instead of reducing the fuel supply to all cylinders in partial-load operation, depending on the requirements, only the power of individual cylinders is reduced to "zero power" through the manipulation of the fuel supply and ignition, while the other cylinders are fired normally. A method of detecting combustion misfires in an internal-combustion engine, includes the following steps: variably actuating valve drives of the engine by an electronic engine control; performing a load-dependent control with the control system by a cylinder-control program; the load-dependent control includes the step of reducing power in at least one cylinder by separately affecting ignition and fuel supply thereto; detecting, in the control system by the cylinder-control program, the cylinder of reduced power with a cylinder-identification signal; at predeterminable intervals detecting, from signals obtained in the preceding step, resulting deviations of predetermined operating data as normal operation; detecting, as combustion misfires, deviations of the predetermined operating data from the normal operation obtained in the preceding step; and generating a setting signal upon detecting deviations in the preceding step.