Method for regulating the fuel / air ratio for an internal combustion engine

A method is presented for the fuel / air mixture adjustment for an internal combustion engine with a catalytic converter and at least one arranged downstream of the catalyst exhaust gas sensor that provides a first information about the oxygen content of the exhaust gas, which affects the adjustment of the fuel / air mixture. The method is characterized in that a second information on the existing downstream of the catalyst in the exhaust gas hydrogen is formed, and in that the second information influences the setting of the fuel / air mixture. The method allows detection of hydrogen after the catalyst and a compensation of the unwanted influence of hydrogen on the setting caused by a hydrogen cross sensitivity of the exhaust gas probe in conjunction with the occurrence of hydrogen of the fuel / air mixture.