Methods and uses of controlling piston varnish formation in an internal combustion engine

摘要

The use as a piston varnish controlling additive in a fuel composition for a spark- ignition internal combustion engine or a compression-ignition gasoline internal combustion engine of a combination of: a. a hydrocarbyl-substituted aromatic compound; and b. a polyalkylene amine. The fuel composition may also be used for controlling power output, fuel economy, engine wear, piston ring sticking and blow-by.