Fuel additives for treating internal deposits of fuel injectors

A method for reducing an amount of salt deposits on internal components of a fuel injector for a fuel injected diesel engine comprising operating the diesel engine on a fuel composition comprising a major amount of fuel and a minor amount of a reaction product derived from (a) a hydrocarbyl substituted dicarboxylic acid, anhydride, or ester and (b) an amine compound or salt thereof of the formula

• wherein R is selected from the group consisting of hydrogen and a hydrocarbyl group containing from about 1 to about 15 carbon atoms, and R1 is selected from the group consisting of hydrogen and a hydrocarbyl group containing from about 1 to about 20 carbon atoms, wherein the reaction product contains less than one equivalent of an amino triazole group per molecule of reaction product.

A method for preventing plugging of a fuel filter for fuel injectors of a fuel injected diesel engine comprising providing a major amount of fuel and a minor amount of a reaction product derived from (a) a hydrocarbyl substituted dicarboxylic acid, anhydride, or ester and (b) an amine compound or salt thereof of the formula

• wherein R is selected from the group consisting of hydrogen and a hydrocarbyl group containing from about 1 to about 15 carbon atoms, and R1 is selected from the group consisting of hydrogen and a hydrocarbyl group containing from about 1 to about 20 carbon atoms, wherein the reaction product is characterized by an FTIR spectrum having a peak intensity in a region of from about 1630 cm−1 to about 1645 cm−1 that ranges from about 5 to about 45% of peak intensities of other peaks in a region of from about 1500 cm−1 to about 1800 cm−1, and wherein the reaction product contains less than one equivalent of an amino triazole group per molecule of reaction product.