The primary goal for this paper is to investigate the effect of biodiesel from WCO on combustion performance and exhaust emission analysis of a direct injection diesel engine. The experiment has been conducted at variable engine speed, constant load and at compression ratios of 17.7. Three types of biodiesel from WCO are tested, which consist of different blending ratio percentage (5%, 20% and 100%) and labelled as B5, B20 and B100 respectively and diesel was used as a comparison purposes. In the end, results show that B5 and B20 show a close resemblance with diesel especially in terms of exhaust emissions
