Over the last few decades, research has focused on reducing environmental pollutants through the use of biodiesel blends, which have become a more important factor in transportation fuels due to their ecofriendliness. These biodiesel blends have higher density and viscosity than diesel, which is a significant barrier to commercial biodiesel exploitation. In this work, various fuel sources, such as sunflower oil and palm oil, were prepared for biodiesel in various proportions. Experimentally, the effects of various concentrations of biodiesel blends on efficiency and CO, NOx, and smoke opacity characteristics were investigated. The results revealed that the addition of ethanol to balm/sunflower oil biodiesel improves efficiency due to the good combustion process. The P5S5D85E10 bio diesel showed better efficiency with lower emissions for all the load conditions. At maximum loaded condition, P5S5D85E10 increased efficiency by 11% and P5S5D85E5 increased efficiency by 5% when compared to P5S5D90 biodiesel. Overall, palm/biodiesel fuel emission results like CO, NOx, and smoke opacity are reduced with ethanol addition.