A method for specifying a malfunction of an exhaust gas recirculation system of an internal combustion engine of a motor vehicle, including: setting a first operating point of the engine and a first operating state of the fresh air/exhaust gas system as vehicle conditioning in a first measurement setting; measuring volumetric efficiencies of the engine for the first measurement setting and for at least one additional measurement setting, and comparing the measured volumetric efficiencies with an engine characteristics map stored in a memory unit for volumetric efficiency values of the engine, and ascertaining whether a malfunction is present during the exhaust gas recirculation process based on the comparison; and specifying the malfunction of the exhaust gas recirculation system while taking into account the measuring results for the first measurement setting and for the at least one additional measurement setting and the stored engine characteristics map for volumetric efficiency values.