<div class="htmlview paragraph">Multifunctional gasoline additives in use today fall in two general categories, the conventional type and the newer detergent-dispersant additives. The value of the detergent-dispersant lies in its ability not only to keep the carburetor clean but also to minimize the buildup of hard refractory deposits on automotive intake valves and to supplement the cleaning power of the engine oil.</div> <div class="htmlview paragraph">Engine tests confirm the effect of the detergent-dispersant. Cleanliness is enhanced in standard tests designed to measure lubricant performance under low and medium temperature engine operation. Intake valve deposits are modified in laboratory and field tests.</div> <div class="htmlview paragraph">Bench scale tests show that when the detergent-dispersant is properly formulated, treated fuels may be satisfactorily handled by refiners in storage and distribution systems.</div>