OPERATING STATE DETERMINATION DEVICE FOR ENGINE, VEHICLE, OPERATING STATE DETERMINATION METHOD FOR ENGINE

A temporal change of a turbo rotation speed of a turbocharger is detected for each cycle of an engine. A first vibration component corresponding to each of cylinders is specified from a pulsation component included in the temporal change of the turbo rotation speed, and the first vibration components for each of the cylinders are integrated over a plurality of cycles. A variation of combustion states in the plurality of cylinders is calculated by comparing integration results among the cylinders.