| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide technology of enabling suitable fuel addition irrespective of fuel property in an exhaust emission control system of an internal combustion engine equipped with a fuel addition valve for adding fuel to exhaust gas of the internal combustion. <P>SOLUTION: In the exhaust emission control system of the internal combustion engine equipped with the fuel addition valve for adding using fuel of the internal combustion engine to exhaust gas upstream of an exhaust emission control device, operation of the fuel addition valve is permitted on the condition that temperature of the exhaust emission control device is equal to or higher than a base temperature Tbase, and the base temperature Tbase is varied according to minimum evaporation temperature Tmin of fuel. According to the invention, the operation of the fuel addition valve is permitted only when fuel added from the fuel addition valve can evaporate, and the fuel added from the fuel addition valve does not attach to the fuel addition valve or the inner wall surface of an exhaust passage. As a result, clogging of the fuel addition valve and shortage of fuel supplied to the exhaust emission control device are inhibited. <P>COPYRIGHT: (C)2008,JPO&INPIT |
