Patent ID: 10704504

Abstract:
A method of operating an engine having an intake manifold, an exhaust manifold, a crankshaft, a plurality of working cylinders each having at least one intake valve and at least one exhaust valve, and an exhaust gas recirculation conduit providing fluid communication between the intake manifold and the exhaust manifold. The method includes: while the engine is operating, in response to a no engine torque request, deactivating a number of the working cylinders such that none of the deactivated working cylinders are fired and no air is pumped through the deactivated working cylinders as the crankshaft rotates, operating at least one of the plurality of working cylinders that is not deactivated to pump air through the non-deactivated working cylinder, and controlling gas flow through the exhaust gas recirculation conduit to circulate air pumped through the non-deactivated working cylinder to the intake manifold.