Method and device for controlling a combustion engine capable of lean running

Control of a lean-runnable vehicular internal combustion engine (10) with a downstream catalyst (14, 16) is such that lean running at air/fuel ratio (lambda) above 1 is effected within an allowed lean temperature range (Tm) for at least one of the catalysis temperatures, the lean running also being temporarily allowed above the Tm range when an emission threshold value is observed. An Independent claim is also included for apparatus for control of a lean-runnable vehicular internal combustion engine (10) (not further specified).