Patent ID: 7073465

Claim:
A method for operating an internal combustion engine having at least one adsorption catalyst in at least one exhaust branch, and having at least one exhaust-gas recirculation duct, which has an exhaust-gas recirculation valve and feeds exhaust gas from the at least one exhaust branch back into at least one air-supply duct, the method comprising: ascertaining a concentration of pollutant stored in the at least one adsorption catalyst in a first operating state of the internal combustion engine when the exhaust-gas recirculation valve is at least partially open, to yield a first value for a pollutant level; ascertaining, in a second operating state of the internal combustion engine, a second value for the pollutant level in the at least one adsorption catalyst when the exhaust-gas recirculation valve is closed; comparing the first value of the pollutant level to the second value of the pollutant level; and carrying out at least one of a diagnosis and an adaptation of an exhaust-gas recirculation system formed by the at least one exhaust-gas recirculation duct, along with the exhaust-gas recirculation valve and drive circuit, as a function of the comparing.