An experimental screening of non-nitrogen containing ignition improvers was conducted to investigate the possible use of diesel/alcohol fuel blends in an unmodified CI engine. The five non-nitrogen containing ignition improvers were: Di-Tertiary Butyl Peroxide; O,O-t-Amyl-O (2-Ethyl hexyl) monoperoxycarbonate; 1,1 Bis-(t-butylperoxy)-3,3,5-trimethylcyclohexane; Tertiary Butyl Hydroperoxide; and t-Amyl Perbenzoate. Alcohol content tested ranged from 10% to 100% by volume. For diesel/alcohol fuel blends containing more than 10% alcohol, BTEs similar to pure diesel could only be achieved with the addition of an ignition improver additive.Since diesel/alcohol blends separate with water addition, additives to improve water addition phase stability were also investigated. The blend employing the preferred ignition improver additive was found to have a greater ability to stay in solution than a control diesel blend without the additive. Higher order alcohols were used as additional surfactants in order to achieve phase stability comparable to commercial gasohol with water contamination.A final preferred Diesohol (i.e. diesel/alcohol) blend containing approximately 67.93% D-2 diesel fuel, 25% ethanol, 5% butanol, 2% ignition improver additive, and 0.07% Lubrizol additive was further tested including gaseous emissions. The blend showed a reduction in NOx, CO2 and soot emissions. HC emissions were increased. CO emissions were reduced at high load but increased at low load.