Controlling method for internal combustion engine involves oscillating combustion of first cylinder set about stoichiometry while second set of cylinders combusts rich air-fuel mixture for selected duration when in second operating mode

摘要

A first set of cylinders continues combustion that oscillates about a stoichiometry while a second set of cylinders combusts rich air-fuel mixture for a selected duration when in second operating mode. The second set of cylinders pumps air without injected fuel when in first operating mode.