Fuel injection system and method

摘要

A fuel injection system includes a first fuel injector that injects a lower-octane fuel into a combustion chamber of an internal combustion engine, and a second fuel injector that injects a higher-octane fuel into an intake passage of the engine. When the engine temperature is equal to or lower than a predetermined temperature during a start-up period of the internal combustion engine, fuel having the lower octane is injected via the first injector while prohibiting injection of the higher octane fuel via the second fuel injector.