A non-metallic organic diesel fuel additive was investigated, Energy Plus D 2000, which is marketed as a fuel economy additive, where typical fuel economy benefits are 10%. The influence of this additive on diesel engine pollution was investigated using a Perkins 4-236 NA DI diesel engine. The additive was found to markedly reduce the particulate emissions by up to 75%. The volatile fraction was reduced slightly more than the carbon and the additive had a strong direct effect on carbon emissions. The optimum level of additive was 0.2%. Higher dosages continued to produce a decreasing level of particulate emissions, but the rate of reduction in the particulates with increase in additive was much lower after 0.2%. However, the active ingredients of the additive are dissolved in kerosene and hence the active component dosage was much less than the nominal dosage. This type of additive warrants further investigation as a means of diesel particulate control.