| 摘要 |
<P>PROBLEM TO BE SOLVED: To achieve quick sulfur poisoning recovery while reducing the increment of a fuel injection amount for an air-fuel ratio of a whole engine to be a theoretical air-fuel ratio or a rich air-fuel ratio during temperature rise control for the sulfur poisoning recovery of a catalyst. <P>SOLUTION: In the temperature rise control for sulfur poisoning recovery of the NOx storing/reducing catalyst 9, part of cylinders is made into a rich air-fuel ratio and the other cylinders are made into a lean air-fuel ratio, and the air-fuel ratio A/F of the whole engine is the theoretical air-fuel ratio. The temperature rise control is executed on condition that a high engine load is predicted to be continued, in accordance with an automobile climbing a hill or its acceleration being a preset value or higher. In such a high engine load condition, homogeneous combustion at the theoretical air-fuel ratio is executed and the amount of fuel required for engine operation becomes a value sufficient for quick temperature rise of the NOx storing/reducing catalyst 9 during the temperature rise control. <P>COPYRIGHT: (C)2004,JPO |
