Polyisobuteneamines of the general formula R1—CH2—NR2R3 in which R1 is a polyisobutyl radical which is derived from isobutene and up to 20% by weight of n-butene and has a number-average molecular weight Mn of from 600 to 770, and R2 and R3 are each independently hydrogen, a C1-C18-alkyl, C2-C18-alkenyl, C4-C18-cycloalkyl, C1-C18-alkylaryl, hydroxy-C1-C18-alkyl, poly(oxyalkyl), polyalkylenepolyamine or polyalkyleneimine radical or, together with the nitrogen atom to which they are bonded, are a heterocyclic ring are suitable as detergents in gasoline fuels, reduce valve sticking and improve the compatibility of the detergents with carrier oils and compatibility in fuel compositions which comprise a mineral fuel content and C1-C4-alkanols.