A fuel additive is formed from dispersions including an organic phase, at least one amphiphlic agent and solid objects based on particles of an iron compound in the crystallized form with a small size, as a fuel additive. The particles have an average size D.sub.DRX of less than or equal to 7 nm measured by X-ray diffraction, and at least 80% by number of the particles have a size D.sub.MET of less than or equal to 7 nm measured by transmission electron microscopy.

The present invention relates to novel uses of corrosion inhibitors in fuels and lubricants.

Methods for improving the injector performance, unsticking fuel injectors, and reducing an amount of alkali metal carboxylate deposits on internal components of fuel injectors. The method includes operating the diesel engine on a fuel composition comprising a major amount of diesel fuel and from about 45 to about 550 ppm by weight based on a total weight of fuel composition of a fuel additive consisting essentially of a compound of the formula

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wherein R is an alkyl or alkenyl group containing from 20 to 170 carbon atoms. The additive has a total acid number (TAN) ranging from about 50 to about 290 mg KOH/g. Fuel injectors of the fuel injected diesel engine have an average injector hole diameter of less than 160 m and an average smallest clearance between injector needle and injector barrel/casing of less than about 10 m.

A fuel additive composition comprises (a) a Mannich reaction product and (b) a polyetheramine where the weight ratio on an actives basis of component (a) to component (b) is 1:4-10. A fuel composition and a method for removing intake valve deposits and combustion chamber deposits in a spark-ignited internal combustion engine comprise the fuel additive composition which is very effective in removing the deposits.

The disclosed technology relates to a concentrated multi-functional additive that can be continuously dosed in internal combustion engines.

The present technology is related to amide or ester containing quaternary ammonium salts having a hydrocarbyl substituent of number average molecular weight ranging from 300 to 750, and the use of such quaternary ammonium salts in fuel compositions to improve the water shedding performance of the fuel composition.

The present technology is related to imidazole containing quaternary ammonium salts and the use of such quaternary ammonium salts in compositions to improve the water shedding performance of the compositions.

The present technology is related to imide containing quaternary ammonium salts having a hydrocarbyl substituent of number average molecular weight ranging from 300 to 750, and the use of such quaternary ammonium salts in fuel compositions to improve the water shedding performance of the fuel composition.

The present technology is related to imide containing quaternary ammonium salts having a hydrocarbyl substituent of number average molecular weight of 1300 to 3000, and the use of such quaternary ammonium salts in fuel compositions or lubricating compositions to improve the water shedding performance of the fuel or lubricant composition.

The present technology is related to quaternary ammonium salts prepared with alcohol functionalized and/or C.sub.4 to C.sub.20 epoxide quaternizing agents, such as, for example, glycidol and 1,2-butylene oxide, and the use of such quaternary ammonium salts in fuel compositions to improve the water shedding performance of the fuel composition.