The increasing price of conventional diesel fuel, its deficiency, and the injurious outcome of combustion produced contaminants seem to make different sources more fascinating. Leucas zeylanica plant is noncomestible in nature and available abundantly. Leucas zeylanica methyl ester is renewable and least polluting fuel, which can supplement fossil fuels with unmodified engine condition. The existing experimentation assesses the performance and emission analysis by using various blends of leucas zeylanica methyl ester, diesel, and diesel additives like 2-ethylhexyl nitrate. This experimental investigation gives less engine emission and better performance as compared with mineral diesel. In the radical portion of this investigation, fuzzy-based Taguchi optimization for predicting the optimum input blends results in the optimum combination of performance and emissions parameter.