An engine ECU executes a program including the steps of: selecting a map
for a warm state or a map for a cold state based on an engine coolant
temperature after an engine is started and rapid catalyst warm-up ends;
calculating DI ratio r; calculating when to inject fuel from an intake
manifold injector as time in synchronization with air intake if a load
factor is equal to or greater than a threshold value and fuel is injected
from injectors at a ratio predetermined therebetween; and otherwise
calculating when to inject fuel from the intake manifold injector as
during a period in which an intake valve is closed.