Method and apparatus for adaptation of a dynamic model of an exhaust gas probe

The invention relates to a method and an apparatus for adaptation of a dynamic model of an exhaust gas probe which is part of an exhaust passage of an internal combustion engine and with a lambda value is determined for controlling an air-fuel composition, said parallel in a control device or in a diagnostic device of the internal combustion engine to a simulated lambda value is calculated from a user function of both the simulated and the measured lambda value is used. According to the invention is provided that the current vehicle operating determined by evaluating a change in signal upon excitation of the system step response of the exhaust probe and the dynamic model of the exhaust probe is adapted on the basis of these results. The invention serves to determine the actual response of the exhaust gas sensor and the correction of the model parameters of the calculated lambda value and thus to improve the match between the measured and modeled lambda value as long as it still seems to make sense from the perspective of the user function.