A method and system for controlling an engine having a turbocharger with at least two discrete positions and exhaust gas recirculation (EGR). The method includes producing a control signal to the turbocharger. The signal has two discrete levels. One of such levels is selected to provide a proper flow of air through the turbocharger to an intake of the engine and such selected level is modulated between such two levels over time to provide, over time, a proper pressure at an input of the EGR to enable a proper flow of exhaust gases from the exhaust of the engine through the EGR back to the intake of the engine. With such method, while there is relatively instantaneous control of the exhaust pressure at the input of the EGR, and hence proper instantaneous control of EGR flow through the EGR. Because of the relatively large inertia, and hence slower response time of the turbocharger to the control signal the turbocharger maintains proper boost flow to the input of the engine via the turbocharger with its accompanying improved fuel efficiency.
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