Direct gasoline injection type spark igniting internal combustion engine with turbocharger and the engine control method

摘要

In a direct gasoline injection type spark igniting internal combustion engine provided with a turbocharger (13) and a catalyst (15), in order to optimize an exhaust gas control, the structure is made such that an optimum exhaust gas control can be obtained only by one control valve (7) by designing an arrangement of a pre catalyst (11), the turbocharger (13) and a bypass exhaust gas passage (21a) and placing a control valve. Further, a stratified operation area is expanded by reducing a capacity of the turbocharger (13), shifting an actuation area to a low capacity side and corresponding to an area of a stratified combustion so as to increase an air amount in the stratified area. Accordingly, since it is possible to early warm up a main catalyst (15) at a time of starting the engine, whereby the exhaust gas is purified, and the air amount in the stratified area is increased, the stratified area expands to a high output side and fuel consumption is improved.