CONTROL DEVICE AND CONTROL METHOD FOR INTERNAL COMBUSTION ENGINES

摘要

A maximum injection amount of a cylinder injection fuel injection valve (8) can cover a region up to a line L2, with respect to a boundary between a stoichiometric air-fuel ratio region A1 and an output air-fuel ratio region A2. The engine is driven by the cylinder injection in the stoichiometric air-fuel ratio A1. A switching line L3 for switching the injection and the stop of a port injection fuel injection valve (41) is set between the two boundary lines L1 and L2. On the high speed and high load side of the switching line L3, the port injection fuel injection valve performs additional fuel injection. The switching of the injection and the stop of the port injection is performed in a condition where the air-fuel ratio becomes the output air-fuel ratio only by the cylinder injection. Accordingly, the increase and the decrease of the total fuel amount is not influenced on the torque. The torque step is small.