| 摘要 |
PROBLEM TO BE SOLVED: To restrain deterioration of a catalyst for exhaust emission control. SOLUTION: Fresh air supply to the catalyst 3 for exhaust emission control from a secondary air supply device is started before fuel cut is actually practiced after a fuel cut practicing condition is established in the case of speedily lowering temperature of the catalyst 3 by supplying fresh air thereto by the secondary air supply device 7 at the time of engine decelerating drive on an exhaust emission control device of an internal combustion engine in which the catalyst 3 is arranged in an engine exhaust passage 2. Consequently, the catalyst temperature is lowered when the fuel cut is practiced and an exhaust gas air fuel ratio becomes lean, and the catalyst is prevented from being exposed in a deteriorating condition of a high temperature lean air fuel ratio.
|
