| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an engine control device for optimizing the purification of exhaust gas by accurately diagnosing a lean NOx catalyst with its NOx storing performance and its O<SB>2</SB>storing performance separated from each other and reflecting the diagnosis result on the control of the lean NOx catalyst. <P>SOLUTION: The engine control device has the lean NOx catalyst for storing NOx exhausted from an engine during lean-operation and desorbing and purifying the stored NOx during rich-operation and an O<SB>2</SB>sensor arranged on the downstream side of the lean NOx catalyst. It comprises a means for computing a stored NOx amount A1 of the lean NOx catalyst and a means for computing a stored O<SB>2</SB>amount B1 of the lean NOx catalyst. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
