PURPOSE: To improve stability of combustion without deterioration of fuel consumption, when fuel cut is executed only for some cylinders at reducing engine speed.
CONSTITUTION: In addition to first fuel injection valves 51 to infect fuel into intake passages 21(21A, 21B), second fuel injection valves 52 to infect fuel into respective cylinders are provided. It is determined according to running condition of the engine which of the first fuel injection valves 51 and the second fuel injection valves 52 are to be operated. When at reducing engine speed fuel is cut off only for some cylinders, the second fuel infection valves 52 are only operated to inject fuel. Fuel injected with the second fuel injection valve 52 is stratified, and hence stability of combustion is improved.
NAKANE HISANORI
AKATSUKA YASUSHI
SHIOMI KAZUHIRO
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