A method for operating an internal combustion engine (100), particularly of a motor vehicle, operated with a gas as fuel, a lambda value of an air/fuel mixture being regulated by means of lambda control as a function of a signal from a lambda probe (130), and, when a lean/rich jump is detected by the lambda probe (130), a mixture control factor (GRF) which controls the mixture composition being varied at least for a predeterminable time such that a shift of the lambda air ratio toward rich is caused, is characterized in that the mixture control factor (GRF) is varied in such a way that an additional defined shift of the lambda air ratio toward rich is caused.