Mani Ghanbari - Department of Mechanical Engineering of Agricultural Machinery, Faculty of Agricultural Engineering, Technical and Vocational University (TVU), Tehran, Iran.
Lotfali Mozafarivanani - Department of Auto Mechanic, Faculty of Mechanical Engineering, Technical and vocational University (TVU), Tehran, Iran.
Masoud Dehghanisoufi - Department of Agrotechnology, College of Abouraihan, University of Tehran, Tehran, Iran.

The fuel system in internal combustion engines is one of the most accurate and sensitive parts and its operation has a significant effect on the quality of combustion process and the content of exhaust emissions. In this study, the effect of fuel filter life on lambda and exhaust emissions of engine has been investigated using the response surface method (RSM). The results showed that the elevated values of lambda (۱.۰۴۲) and CO (۰.۸۸%) occur at the engine speed of ۵۰۰۰ rpm with a fuel filter life (FFL) of ۶۰,۰۰۰ km. Also, the highest CO۲ content was obtained as ۱۴.۹% at ۱۰۰۰ rpm with a new fuel filter (۰ km). Moreover, the highest amount of HC emission (۲۱۵ ppm) was measured at ۱۰۰۰ rpm and using FFL of ۶۰,۰۰۰ km. The results showed that increasing the fuel filter life increases the exhaust emissions of the engine. Therefore, timely replacement of the fuel filter, in addition to increasing engine performance, will reduce air pollution, especially in big cities.

Gasoline Engine, Fuel Filter, Lambda, Exhaust Emission