Method for operating a multicylinder internal combustion engine with direct injection in the cylinder

摘要

An IC engine with direct fuel injection has added control selecting one cylinder to vary the lambda value to produce a lean burn. Excess oxygen passes into the exhaust duct while another cylinder is controlled via its lambda value to produce a rich burn, passing excess fuel into the exhaust duct. This provides a controlled burn to raise the temperature of the catalytic converter to the operating value. The change in burn conditions for the selected cylinders is transitory. The raised temperature in the catalytic converter reduces emission products during cold starting and also removes excess sulphur deposits during normal operation.