Patent ID: 7112230

Claim:
A method for controlling injector deposits in a direct injection gasoline engine which comprises introducing into a direct injection gasoline engine with the combustion intake charge a spark-ignition fuel composition comprising a) a spark-ignition fuel and b) a fuel-soluble compound having the formula (I): wherein R 1 and R 2 are independently C 1-4 alkyl, R 3 is a radical of the formula C m H 2m wherein m is an integer of 2 to 6, R 4 and R 5 are each independently (i) wherein R 6 is selected from the group consisting of hydrogen and C 1-4 alkyls and R 7 is selected from the group consisting of hydrogen and C 1-30 alkyl, (ii) wherein R 8 is a saturated or unsaturated, linear, branched or cyclic, C 7-23 hydrocarbyl group or (iii) wherein R 4 and R 5 together with the nitrogen atom to which they are bonded, form a cyclic ring in which further hetero atoms may be incorporated.