Impact of Fuel Additives on Intake Valve Deposits, Combustion Chamber Deposits and Emissions

Gasoline components play a prime role in the formation of deposits on engine components. In order to reduce the deposit forming tendency of fuels, oil marketing companies dope the multi functional additives in gasoline for trouble free operation over a longer period of time. For assessing intake valve deposits and combustion chamber deposits forming tendency of gasoline/additised gasoline, Coordination European Council (CEC) has established the engine test method CEC F-20-A-98 on Mercedes Benz M 111 gasoline engine. The above test method is able to discriminate IVD and CCD formation tendency with neat fuel and additised fuel. In the present work, an effort has been made to discriminate between the additives and an attempt has also been made to understand their impact on emission characteristics.

Gasoline treated with multi functional additives reduced the intake valve deposits substantially and decreased the CO and HC emissions, whereas multifunctional additives increased combustion chamber deposits. The intake valve and combustion chamber deposits formation and exhaust emissions depend upon the treat rate and components of multifunctional additives blended with gasoline. The dosage of multi functional additives in gasoline was optimized for reducing IVD and CCD in order to maintain the engine performance and emission characteristics over a period of time.