| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a catalyst deterioration detection device capable of materializing robust catalyst deterioration detection control by coping with hydrogen and unburned HC giving bad influence on an exhaust gas sensor in an initial stage. <P>SOLUTION: ECU 1 executing active deterioration detection control for detecting deterioration of a three-way catalyst 22 using output of an A/F sensor 23 and an oxygen sensor 24 in an internal combustion engine system 100 provided with an air current control valve 58 for improving a condition of combustion in the internal combustion engine 50, an A/F sensor 23 and an oxygen sensor 24 detecting oxygen in exhaust gas, and the three-way catalyst 22 purifying exhaust gas, is provided with a deterioration detection control permission means permitting execution of active deterioration detection control according to the degree of combustion improvement by the air current control valve 58. The deterioration detection control permission means permits execution of active deterioration detection control when a valve opening condition of the air current control valve 58 is half open. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
