The fuel injection system controls the air/fuel ratio around the stoichiometry under any driving conditions by injecting a specific amount of fuel at appropriate timing, based on signals from the engine ECU. The engine ECU determines the amount of fuel injection based on the amount of air detected by the air system and driving conditions.

DENSO’s latest injector, launched in 2002, injects fuel with a fine fuel spray particle size, around 50 µm, preventing an increase in the amount of fuel injected during engine warming.