Patent ID: 7704289
Filing Date: 2010-04-27
Classification: C10L

Abstract:
1. A method to clean up or keep clean a fuel system of a direct injection spark-ignited engine, comprising: operating the engine with a fuel composition comprising a liquid fuel; and a fuel additive composition comprising at least one nitrogen-containing dispersant; and optionally a polyether fluidizer, wherein a molecular volume factor for the dispersant is about 50 or greater, a modified hydrophilic lipophilic balance (HLBm) value for the dispersant or for the dispersant and the fluidizer is greater than 50, the concentration of nitrogen in the fuel composition from the dispersant is about 0.15 to about 50 ppm by weight, and the concentration of active components in the fuel composition from the dispersant or the dispersant and the fluidizer is about 10 to about 10,000 ppm by weight.