A diesel fuel composition comprising as an additive an ester compound which is the reaction product of an optionally substituted polycarboxylic acid or an anhydride thereof and a polyhydric alcohol of formula H—(OR).sub.n—OH, wherein R is an optionally substituted alkylene group and n is at least 1.

The present invention relates to the use, for improving the detergency properties of a liquid fuel composition comprising one or more detergent additives, of an additive consisting of one or more hydrocarbon compound(s) comprising from 2 to 10 carbon atoms and two hydroxyl functions.

The present invention also relates to a method for improving the cleanliness of and/or for cleaning at least one inner portion of an internal combustion engine supplied with a liquid fuel comprising one or more detergent additives, wherein such a hydrocarbon compound is added to the fuel composition.

Gasoline Direct Injection (GDI) engines require gasoline particulate filters (GPFs) as a key component of the emissions control system to reduce particulate emissions. GPFs are known to have poor initial performance, with performance increasing after the filter develops a cake. This poor initial performance make it impossible to accurately assess vehicle emissions performance at the mileage requirements for vehicle certification. Compositions and methods are disclosed to improve filtration efficiency in a fresh or low mileage GPF.

Gasoline Direct Injection (GDI) engines require gasoline particulate filters (GPFs) as a key component of the emissions control system to reduce particulate emissions. GPFs are known to have poor initial performance, with performance increasing after the filter develops a cake. This poor initial performance make it impossible to accurately assess vehicle emissions performance at the mileage requirements for vehicle certification. Compositions and methods are disclosed to improve filtration efficiency in a fresh or low mileage GPF.

The present disclosure relates to methods and fuel compositions for reducing or eliminating fuel injector deposits in high pressure gasoline engines. The fuel compositions include gasoline and a synergistic combination of a fuel injector clean-up mixture including a heterocyclic amine, diamine, or open chain derivative thereof and a hydrocarbyl substituted dicarboxylic anhydride derivative selected from a diamide, acid/amide, acid/ester, diacid, amide/ester, diester, and imide.

The present disclosure relates to methods and fuel compositions for reducing or eliminating fuel injector deposits in high pressure gasoline engines. The fuel compositions include gasoline and a synergistic combination of a fuel injector clean-up mixture including a heterocyclic amine, diamine, or open chain derivative thereof and a hydrocarbyl substituted dicarboxylic anhydride derivative selected from a diamide, acid/amide, acid/ester, diacid, amide/ester, diester, and imide.

The testing of various chemicals has yielded new chemicals and chemical mixtures for the use of removing carbon deposits from the internal combustion engine. Some of these chemicals and chemical mixtures have proven to work better across many different carbon types than other chemicals that were tested. These chemical terpenes are typically produced from plants. One standard terpene mixture is known as turpentine. The chemical turpentine and chemicals found in turpentine have been determined, through our research and testing, to be extremely effective at removing the carbon that is produced within the internal combustion engine.

The testing of various chemicals has yielded new chemicals and chemical mixtures for the use of removing carbon deposits from the internal combustion engine. Some of these chemicals and chemical mixtures have proven to work better across many different carbon types than other chemicals that were tested. These chemical terpenes are typically produced from plants. One standard terpene mixture is known as turpentine. The chemical turpentine and chemicals found in turpentine have been determined, through our research and testing, to be extremely effective at removing the carbon that is produced within the internal combustion engine.

The present invention relates to the use of a fuel composition comprising at least 85% by weight of one or more hydrocarbon fractions consisting of one or more hydrotreated vegetable oils, said fraction(s) having a distillation range between 100 and 400° C. and having a paraffin content greater than or equal to 90% by weight, for reducing the deposits present in the internal parts of a compression ignition engine (or diesel engine). The present invention also relates to a method for cleaning the deposits present in the internal parts of a compression ignition engine using such a composition.

The present invention relates to the use of a fuel composition comprising at least 85% by weight of one or more hydrocarbon fractions consisting of one or more hydrotreated vegetable oils, said fraction(s) having a distillation range between 100 and 400° C. and having a paraffin content greater than or equal to 90% by weight, for reducing the deposits present in the internal parts of a compression ignition engine (or diesel engine). The present invention also relates to a method for cleaning the deposits present in the internal parts of a compression ignition engine using such a composition.