EXHAUST PURIFICATION DEVICE FOR INTRACYLINDRICAL INJECTION-TYPE SPARK-IGNITION INTERNAL COMBUSTION ENGINE
DRIVE
September 24, 2003
When an internal combustion engine is in a cold state (S12), fuel is injected during compression stroke with burn air/fuel ratio controlled so as to produce a slight lean air/fuel mixture equivalent to or slightly leaner than a stoichiometric air/fuel mixture (compression S/L operation) (S14), and also exhaust gas flow is restrained (S16).
Discussion in the ATmosphere