Internal combustion engine, with - at least one combustion chamber, to which air a combustion gas and a stabilizing gas can be supplied, - at least one sensor (3, 14) for measuring at least one engine variable (λ, p), wherein the at least one sensor includes at least one sensor, preferably realized as a pressure sensor, to measure, as an engine variable, at least one pressure of a mixture of combustion gas, stabilizing gas and air that is present in the at least one combustion chamber during the combustion, as well as - an open-loop or closed-loop control device, which is connected to the at least one sensor and which is designed to control by open-loop or closed-loop control, by means of the open-loop or closed-loop control device and in dependence on the at least one engine variable (λ, p), a quantity of stabilizing gas supplied to the at least one combustion chamber, characterized in that', in addition, a lambda probe and/or an oxygen sensor and/or a carbon monoxide probe is provided to measure a lambda value (λ) as an engine variable and in that the open-loop or closed-loop control device is designed - to calculate from the measurement values of the at least one sensor for measuring the at least one pressure (p) of the mixture of combustion gas, stabilizing gas and air that is present in the at least one combustion chamber during the combustion, as an engine variable, a time variable that is characteristic of the speed of combustion of the gas present in the at least one combustion chamber, and, in dependence of the at least one time variable, to control by an open-loop or closed-loop control the quantity of the stabilizing gas supplied to the at least one combustion chamber, as well as - to increase the quantity of the supplied stabilizing gas if a lower lambda limit value (λ min) is undershot. - at least one combustion chamber, to which air a combustion gas and a stabilizing gas can be supplied, - at least one sensor (3, 14) for measuring at least one engine variable (λ, p), wherein the at least one sensor includes at least one sensor, preferably realized as a pressure sensor, to measure, as an engine variable, at least one pressure of a mixture of combustion gas, stabilizing gas and air that is present in the at least one combustion chamber during the combustion, as well as - an open-loop or closed-loop control device, which is connected to the at least one sensor and which is designed to control by open-loop or closed-loop control, by means of the open-loop or closed-loop control device and in dependence on the at least one engine variable (λ, p), a quantity of stabilizing gas supplied to the at least one combustion chamber, - to calculate from the measurement values of the at least one sensor for measuring the at least one pressure (p) of the mixture of combustion gas, stabilizing gas and air that is present in the at least one combustion chamber during the combustion, as an engine variable, a time variable that is characteristic of the speed of combustion of the gas present in the at least one combustion chamber, and, in dependence of the at least one time variable, to control by an open-loop or closed-loop control the quantity of the stabilizing gas supplied to the at least one combustion chamber, as well as - to increase the quantity of the supplied stabilizing gas if a lower lambda limit value (λ min) is undershot.