The good replacement of diesel is found to be biodiesel which is a renewable source and the existing engine can run with the biodiesel without doing any modifications. The various emission technologies have been constantly being tested by the researchers to lower the value of exhaust emission by diesel. Owing to this different organics blends along with the mixing of additives are keep on being tested to reduce the emission and to bring slight increase in the performance level. In our diversity the biodiesel is found to be more abundantly available. The methyl ester that is tested here is the Spirulina methyl ester which can grow in fresh water and also in the salt water. The Spirulina physically appears to swirl and it is in the form of helix and so it is named as Spirulina. Likewise the Jatropha and rapeseed oil, the extraction and preparing the biodiesel from the Spirulina also has the same method. The experiment was carried out in a single hole and 3 hole nozzle by using the Spirulina B20 blend and neat diesel in order to find out the good spray characteristics and also the internal flow pattern. Preheating of the Spirulina B20 blend was also done and the test was carried out in the single hole and 3 hole nozzle. The results showed that the Spirulina B20 with 3hole nozzle and preheated at 60° C gave the performance value nearer to diesel and also the emission characteristics were lowered to a considerable level. © 2023 Elsevier B.V., All rights reserved.