摘要 |
A spark ignition type internal combustion engine of the present invention is provided with a variable closing timing mechanism which can change a closing timing of an intake valve after suction bottom dead center wherein the amount of intake air fed into a combustion chamber is controlled mainly by changing the closing timing of the intake valve. At the time of engine cold start, the closing timing of the intake valve is advanced compared with the time of engine warm operation. At the time of engine cold start, the air-fuel mixture which is taken into a combustion chamber is blown back into the engine intake passage whereby the air-fuel ratio varies among cylinders, but according to the spark ignition type internal combustion engine of the present invention, it is possible to suppress such variation in the air-fuel ratio among cylinders.
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