The detrimental environmental impacts of the use of conventional fuels, both gasoline and diesel, have spurred researchers to seek alternative fuels that minimize these environmental impacts and risks. Therefore, this research focuses on the incorporation of various additives in gasoline to reduce pollutants emission and to enhance fuel economy. Gasoline was blended with ethanol and butanol at various ratios to investigate their influence on the engine performance under different operating conditions. The blending ratios of ethanol and butanol to gasoline were 2, 5, 10, 15 and 20%. The fuel consumption of the engine and pollutants emission was measured for all blends at different engine speeds under low loading. The experimental results showed a clear reduction in pollutants emitted from the engine 13.7% for carbon monoxide and 25.2% for hydrocarbons as well as fuel consumption by 8.22%. However, the engine power was negatively impacted and could reach up to 11.1% for the fuel blends. (C) 2019 Elsevier Ltd. All rights reserved.