| 摘要 |
PROBLEM TO BE SOLVED: To enhance an early activation of catalyst while maximally restraining discharge of HC an atmosphere until the catalyst for exhaust emission is activated. SOLUTION: At engine cooling time, a separate injection is carried out such that a part of fuel is injected in an intake stroke, and a remained fuel is injected in a compression stroke. At this time, separation ratio HSRATIO of separate injection is set so as to reduce HC in an exhaust air until a catalyst temperature CTEMP becomes more than a first predetermined temperature CTEMP1 from a cold start, and an ignition timing ADV is set so as to increase a temperature of the exhaust air thereby enhancing increase of the catalyst temperature (S4). Until the catalyst temperature CTEMP becomes more than a second predetermined temperature TEMP2 since the time the catalyst temperature CTEMP has become more than the first predetermined temperature CTEMP1, the separation ratio HSRATIO and the ignition timing ADV are set so as to increase CO and O2 components in the exhaust air, and the catalyst is activated at a comparatively low temperature (S5).
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