To materialize HC reduction by early stage activation of a catalyst and after burn by great retardation of ignition timing and to avoid deterioration of HC in ultra retard combustion in a stage where oil and water temperature is low.
The ultra retard combustion in which ignition timing ADV is retarded to 10-50 ATDC, first fuel injection I1 is performed in compression stroke, and second fuel injection I2 is performed in an expansion stroke at timing advanced from ignition timing ADV by 10-20 CA is carried out in cold start of an internal combustion engine during which early stage temperature rise of a catalytic converter is demanded. Compact air fuel mixture lump is formed at a part of combustion chamber near a spark plug by the first injection, rich air fuel mixture lump is locally formed in a part near the spark plug inside thereof by the second injection, and ignition is done under these conditions. However, ultra retard combustion is inhibited when engine oil water temperature is lower than predetermined oil water temperature tolerance.
SAKAI AKIKAZU
HORIGOME TAIZO
Hiromichi Kobayashi
Tomioka Kiyoshi