An exhaust gas recirculation system for an internal combustion engine employs a recirculation control valve in a passageway connecting the engine exhaust passage to the engine intake passage downstream from the throttle valve. An air conduit having an air control valve therein furnishes atmospheric air to the intake passage downstream from the throttle valve. Vacuum responsive actuators are provided for each of the control valves and they are operated by vacuum pressure regulated by a regulating valve, which regulating valve is responsive to differential pressure between vacuum intensity in the intake passage upstream from said throttle valve and modified atmospheric pressure. The modified atmospheric pressure is obtained downstream of a restriction in the air conduit.
