Abstract: A fuel oil detergent which efficiently constricts precipitate formation and octane number requirement increase in a carburetor, injector, and inlet system of an internal combustion engine, i.e., a hydropoly(oxyalkylene) oxyalkyl amine based compound, a process for preparing the compound, and a fuel oil composition including the compound.

Abstract: The present invention relates to derivatives of polyalkenyl amine substituted with numerous hydroxy groups of the following formula (I) useful as a novel fuel detergent. ##STR1## wherein polyalkenyl denotes a branched alkyl derived from polyolefin which has a molecular weight of 400.about.5,000 and is prepared with olefin having 2 to 6 carbon atoms; m is an integer ranging from 2 to 10, R.sup.1, R.sup.2 and R.sup.3 may be identical or different, and represent a hydrogen atom or a linear or branched alkyl having 1 to 4 carbon atoms: R.sup.4 and R.sup.5 may be identical or different, and denote a hydrogen atom, a C.sub.1 -C.sub.10 alkyl group, a hydroxyalkyl, a phenyl, naphthyl, an aminoalkyl of formula (II) or a polyaminoalkylene of formula (III) ##STR2## wherein R.sup.6 denotes a C.sub.2 -C.sub.10 alkylene group: R.sup.7 and R.sup.8 may be identical or different, and denote a hydrogen atom, a C.sub.1 -C.sub.10 alkyl group, a phenyl, a naphthyl or a C.sub.1 -C.sub.