Patent attributes
For operating an internal combustion engine a respective lambda adaptation value (LAM_AD) assigned to a respective temperature range is adapted as a function of at least one corrective signal proportion of a lambda controller in relation to a control parameter of the lambda controller if a predetermined condition is fulfilled. The respective lambda adaptation value (LAM_AD) is assigned a respective reference temperature If a predetermined test condition is fulfilled, a check is made as to which of the lambda adaptation values (LAM_AD) was adapted as a function of the at least one corrective signal proportion since the test condition was last fulfilled. A respective lambda adaptation value not adapted as a function of the at least one corrective signal is compared to a range of valid values. If it lies outside the predetermined diverging range of valid values, the non-adapted lambda adaptation value (LAM13 AD) is adapted in a defined manner.