Abstract: A combustion engine has a line (20) for feeding exhaust gases back from the outlet system (3, 3) to the inlet system (2), an EGR valve (17) in the line (20), an exhaust brake valve (50) in the outlet system to increase the pressure in the outlet system upstream therefrom, and a control system (32) for controlling the degree of opening and closing of the valves (17, 50) on the basis of signals which represent the engine's operating state. The control system (32) holds the EGR valve (17) open and the exhaust brake valve (50) in a position which substantially throttles the exhaust gas flow so long as a first signal indicates that the engine has, during its starting, not yet reached a steady operating state. The result is a particularly simple way of appreciably shortening the time the engine takes to reach a steady operating state from a cold start and a corresponding reduction in discharge of emissions.