| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a poisoning restoring technology for suppressing the occurrence of odors accompanying poisoning restoration of exhaust emission control catalysts. <P>SOLUTION: Before a curing period for exhaust emission control catalysts 50a, 50b passes, the poisoning of the exhaust emission control catalysts 50a, 50b is estimated in accordance with engine operating histories, the time when the poisoning is estimated is considered as a SOx poisoning restoration timing, and SOx poisoning restoring control is performed. The SOx poisoning restoring control in accordance with the output of a NOx sensor 25 can be performed even in the curing period, and when the SOx poisoning restoring control in accordance with the output of the NOx sensor 25 is requested in the curing period, the SOx poisoning restoring control is performed while suppressing the release concentration of poisoning components during the SOx poisoning restoring control. Furthermore, the SOx poisoning restoring control in accordance with the engine operating histories thereafter is performed more quickly. <P>COPYRIGHT: (C)2004,JPO |
