In an internal combustion engine with several cylinders, at least one cylinder is configured as a reference cylinder to which an active cylinder pressure sensor is allocated. A passive cylinder pressure sensor is allocated to each of the remaining cylinders. At least one actuating member is assigned to the cylinders. A crankshaft angle sensor is provided. During the quasi-stationary operating mode, the cylinder segment durations are equated, by an actuating member engaging in at least one actuating signal allocated to the respective cylinder. Furthermore, during the quasi-stationary operating mode, the measuring signal of the active sensor is allocated to the respective measuring signals of the passive sensors. As a result, the signal processing of the measuring signals of the passive sensors is adjusted depending on the respective measuring signals of the passive sensors captured during the quasi-stationary operating mode and on the allocated measuring signal of the active sensor.