Various combustion characteristics and properties are studied while selecting a fuel for any engine. The choice of the engine and fuel are highly interrelated. Vegetable oil is one obvious fuel particularly because their fuel properties are closer to diesel fuel. Two important properties, the cetane number and the calorific value are similar to diesel. Hence diesel engines can be operated on vegetable oil without modification. To ascertain the possibility of use of modified karanja oil as fuel for compression ignition engine the performance test were conducted. The comparison of the test fuels made with diesel fuel. Test fuelsâ€™ performance analyzed for esters of karanja oil, blends of karanja oil, and the diesel oil as baseline at varying loads performed at governor controlled speed. The variations in the injection parameters were analyzed to observe its influence on the engine performance with different fuels. Experimental results show that diesel engine gives poor performance at lower Injection Pressure than esterified karanja oil and its blends with diesel. Specific energy consumption is a more reliable parameter for comparison. MEKO and 50KO which shown comparable energy required per kW power than diesel fuel it may be due to lower calorific value of MEKO. Comparable smoke found for karanja oil methyl ester with that of diesel fuel. Smoke emission increases with increase in engine load due to overall richer combustion, longer duration of diffusion combustion phase and reduced oxygen concentration.