Method for operating an internal combustion engine and device for implementing the method

A device for operating an internal combustion engine, in whose exhaust region, in a direction of flow of an exhaust gas, there are situated a first broadband lambda sensor which makes available a first lambda signal, an NOx adsorption catalyst, and a second broadband lambda sensor which makes available a second lambda signal, the NOx adsorption catalyst cyclically storing NOx emissions of the internal combustion engine, the device comprising at least one control unit for performing the following:

• regenerating the NOx adsorption catalyst within the scope of a nominal regeneration by operation of the internal combustion engine using at least one of (a) a rich air/fuel mixture and (b) at least a stoichiometric air/fuel mixture;
• carrying out an intensified regeneration, compared to the nominal regeneration, of the NOx adsorption catalyst by the operation of the internal combustion engine using a rich/stoichiometric air/fuel mixture;
• and
• at an end of the intensified regeneration at a still rich/stoichiometric air/fuel mixture, undertaking at least one of a plausibility check of the first lambda signal using the second lambda signal and a correction of the first lambda signal using the second lambda signal.