To provide a control method for a direct injection spark ignition engine by which stratified charge combustion can be maintained even in a combustion mode change from the stratified charge combustion to homogenous combustion in an expansion stroke.
The direct injection spark ignition engine sets ignition timing and makes spark ignition after passing a compression upper dead center, and sets fuel injection timing at the expansion stroke to perform fuel injection, and thereby the stratified charge combustion in the expansion stroke is realized by these spark ignition and fuel injection. In the direct injection spark ignition engine, when changing the ignition timing, an engine controller (15) includes a fuel injection timing/ignition timing changing process procedure which changes both the fuel injection timing of the fuel injection and the ignition timing after having passed the compression upper dead center with a difference between these timings kept at a given value.
Masahiro Fujii
Masaaki Iida
Yasunari Mita
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