Patent ID: 8316819

Claim:
A method of controlling a spark ignited internal combustion engine having a fuel injector which injects fuel directly into its combustion chamber, comprising: stopping the fuel injection if a desired torque for said engine is a predetermined torque or less and a speed of said engine is a predetermined speed or greater; resuming the fuel injection by injecting a first amount of fuel directly into said combustion chamber during a negative pressure period which is a part of a negative valve overlap period that is after an exhaust valve of said combustion chamber is closed and before an intake valve of said combustion chamber is opened in a cylinder cycle and during which a pressure in said combustion chamber is lower than a pressure when said exhaust valve is closed and injecting a second amount of the fuel into said combustion chamber during an intake period in which said intake valve of said combustion chamber is opened when the engine speed has decreased to said predetermined speed, said second amount being less than said first amount and including zero; and resuming the fuel injection by injecting a third amount of the fuel directly into said combustion chamber during the negative pressure period and injecting a fourth amount of the fuel into said combustion chamber during the intake period when the desired engine torque has increased to said predetermined torque, said third amount being less than said fourth amount and including zero.