Fuel Injection Control - Stratified-Charge Combustion
WARNING: This page is about a different car, the 2017 Nissan Sentra. However, it is still accessible from the selected car via links, so may be relevant.
Stratified-charge combustion is a combustion method which enables extremely lean combustion by injecting fuel in the latter half of a compression process, collecting combustible air-fuel around the spark plug, and forming fuel-free airspace around the mixture.
Right after a start with the engine cold, the catalyst warm-up is accelerated by stratified-charge combustion.