METHOD OF OPERATING A DIRECT INJECTION SPARK-IGNITED ENGINE WITH A FUEL COMPOSITION

摘要

The present invention is directed to a method to clean up or keep clean the fuel system of a direct injection spark-ignited engine by operating the engine with a fuel composition that includes a liquid fuel and a fuel additive composition. The fuel additive composition useful in the present invention has at least one nitrogen-containing dispersant and optionally a fluidizer where the dispersant has a specific lipophilic parameter and the dispersant or the dispersant and the fluidizer have a specific hydrophilic-lipophilic parameter, the dispersant provides about 0.15 to about 50 ppm by weight nitrogen in the fuel composition, and the fluidizer and/or the dispersant provide about 10 to about 10,000 ppm by weight active components in the fuel composition. The method of the present invention is effective in controlling deposits in fuel injectors and combustion chambers of a direct injection spark-ignited engine.