Motor fuel composition

Abstract

Motor fuel compositions having detergent properties are disclosed and claimed which are particularly useful in spark-ignition, internal combustion engines. The fuel compositions of the present invention contain certain additives which either substantially eliminate, mitigate against, or maintain at a low level, deposits which would otherwise form in the carburetor, in the intake valves and ports, and in the combustion chamber, including the spark plugs. Such carburetor and intake system (induction system) deposits are to be avoided since they tend to restrict the flow of air through the carburetor especially at idle and at low speeds and/or cause improper valve closing and sluggish valve action. These conditions produce rough engine idling, stalling, and can also result in excessive hydrocarbon and carbon monoxide exhaust emissions. Combustion chamber deposits are to be avoided since they cause an increase in octane requirement, emissions and cause preignition. The fuel additives of the present invention include for induction system deposit control an ester selected from a dimer or trimer acid ester or from other polycarboxylic acid esters, especially dicarboxylic acid esters.

Dependencies are inferred from the claim text.