A method and a computer program for recognizing and differentiating a flow rate error and a dynamic error of an exhaust gas recirculation system (EGR) of an internal combustion engine. Measured and modeled EGR mass flow signals are each subjected to bandpass filtering using time constants optimized for determining flow rate errors and bandpass filtering using time constants optimized for determining dynamic errors. The energy is determined for each of the filtered signals and an energy quotient is computed between the energies of the signals filtered for dynamic errors and the signals filtered for flow rate errors. A dynamic error and a flow rate error of the exhaust gas recirculation may be recognized and differentiated from one another on the basis of the energy quotients.