A flow control mechanism connected to the intake and exhaust systems of an engine. The mechanism may achieve recirculation of exhaust gases despite varying differential pressures or pulses of pressures. The control mechanism may be connected to a storage device. The pulses may be used to store some of the exhaust gas in the storage device. The exhaust gas needed at the intake manifold may be supplied while the exhaust gas is replenished. The storage may eliminate the necessity of dealing with the pressure pulses and dependent coordination of the flow control mechanism with the pulses.