Abstract: A combustion control system for an internal combustion engine. A control device with a vortex chamber has a tangential inlet connected to a gas supply at substantially atmospheric pressure, a second inlet, and an axial outlet connected directly to the gas inlet opening of the intake manifold. A condenser condenses water from the exhaust gas passing through the exhaust conduit. A gas inlet of a reactor device has a gas inlet connected directly to the exhaust manifold for drawing gas therefrom and an outlet connected to the second inlet of said control device by a conduit. The reactor device includes one or more ejectors for drawing in atmospheric air and for drawing in liquid water from the condenser, and for mixing the atmospheric air and water with gas from the exhaust manifold.