CONTROL DEVICE FOR ENGINE

摘要

PROBLEM TO BE SOLVED: To efficiently purify a great amount of NOx emitted from a NOx trapping material at the beginning of lean-to-rich transition of an air/fuel ratio of an engine. SOLUTION: When NOx is emitted from a NOx trapping material (S4) the quantity of fuel is increased so that separate injection is performed with main injection near a top dead point in compression strokes and subsequent post injection (S8, S9) and a post injection timing Tr2 has a greater retardation at the beginning of starting the post injection and then a smaller retardation (S13, S14).