EXHAUST EMISSION CONTROL DEVICE FOR ENGINE

摘要

PROBLEM TO BE SOLVED: To prevent HC in exhaust gas from passing through a catalyst without being oxidized thereby. SOLUTION: An NOx purifying catalyst 22a and an oxidizing catalyst 22b are arranged in an exhaust passage 20 so that the former is on the upstream side, and the latter is on the downstream side. When the HC quantity in exhaust gas supplied to the catalyst 22a by injection is increased after a main fuel injection performed near the top dead center of compression stroke, the injection timing is retarded more when the temperature of the downstream oxidizing catalyst 22a is low than when it is high.