Method and apparatus for operating a spark-ignited direct fuel injection engine

Article of manufacture, comprising a storage medium having machine-executable code encoded therein to control operation of a spark-ignition, direct fuel injection internal combustion engine to minimize combustion variation, the code comprising:

• code to inject a first fuel pulse directly into an engine cylinder combustion chamber during a combustion cycle;
• code to initiate spark ignition by energizing a spark igniter after a preferred elapsed time after end of the first fuel pulse and prior to injection of a second fuel pulse;
• and,
• code to inject the second fuel pulse directly into the engine cylinder combustion chamber during the combustion cycle to form a stratified charge of fuel-air mixture with an ignitable fuel-air mixture proximal to the spark igniter subsequent to said initiation of spark ignition during a period in time whereat the spark igniter is energized.