Fuel additive for improved performance in fuel injected engines

A method of improving the injector performance of a fuel injected internal combustion engine comprising operating the engine on a fuel composition comprising a major amount of fuel and from about 5 to about 200 ppm by weight based on a total weight of the fuel of a quaternary ammonium salt of a tertiary hydrocarbyl amine and a hydrocarbyl-substituted alkyl-hydroxybenzoate, wherein the quaternary ammonium salt present in the fuel improves an injector needle lift test to at least about 80% flow remaining when measured according to a CEC F-23-01 (XUD-9) test or improve power restoration by at least 100% when measured according to a CEC F98-08 DW10 test, and wherein the hydrocarbyl-substituted alkyl-hydroxybenzoate contains one or more hydrocarbyl substituents providing a total of at least 8 up to about 200 carbon atoms, provided the one or more hydrocarbyl substituents do not contain sulfur, oxygen, or nitrogen atoms.

A method of operating a fuel injected internal combustion engine comprising combusting in the engine a fuel composition comprising a major amount of fuel and from about 5 to about 200 ppm by weight based on a total weight of the fuel of a quaternary ammonium salt of a tertiary hydrocarbyl amine and a hydrocarbyl-substituted alkyl-hydroxybenzoate, wherein the hydrocarbyl-substituted alkyl-hydroxybenzoate contains one or more hydrocarbyl substituents providing a total of at least 8 up to about 200 carbon atoms, provided the one or more hydrocarbyl substituents do not contain sulfur, oxygen, or nitrogen atoms.

An additive concentrate for a fuel for use in a fuel-injected internal combustion engine comprising a quaternary ammonium salt of a tertiary hydrocarbyl amine and a hydrocarbyl-substituted alkyl-hydroxybenzoate and at least one component selected from the group consisting of diluents, carrier fluids, compatibilizers, cetain improvers, corrosion inhibitors, cold flow improvers (CFPP additive), pour point depressants, solvents, demulsifiers, lubricity additives, friction modifiers, amine stabilizers, combustion improvers, dispersants, antioxidants, heat stabilizers, conductivity improvers, metal deactivators, marker dyes, organic nitrate ignition accelerators, and cyclomatic manganese tricarbonyl compounds, wherein the hydrocarbyl-substituted alkyl-hydroxybenzoate contains one or more hydrocarbyl substituents providing a total of at least 8 up to about 200 carbon atoms, provided the one or more hydrocarbyl substituents do not contain sulfur, oxygen, or nitrogen atoms.

A fuel additive compound of the formula

• wherein each of R1, R2, R3, and R4 is selected from a hydrocarbyl group containing from 1 to 200 carbon atoms, and M comprises hydrocarbyl-substituted hydroxybenzoate group.