Experimental Study For The Effect Of The Gasoline Quality On Vehicle Emission And OBD System

With the continuous tightening vehicle emission standards and the application of advanced emission control technologies, the effect of the fuel quality on vehicle emission is increasingly important. Therefore, in the USA, Japan, Europe and other countries and regions, the automotive and petrochemical industries have cooperated to initiate the "Vehicle-Engine-Oil" program. Through their research results, they have established the key index limits of the fuel quality which meet the gradual tightening vehicle emission regulations. With publication of the National Sage III, IV emission standard, the relevant fuel quality index should be established. Since 2004, CATARC has undertaken the "Research on the relation between the fuel quality and vehicle emission"-II program. The main task of the paper is experimental study the effect of the gasoline quality on vehicle emission and OBD system.Through scientific experiment designing, the paper has studied the effect of the gasoline sulfur, olefin on the initial emission of LEV. The research indicate that reduce the olefin content(and increase equivalent aromatic content at the same time)and sulfur content can reduce the HC, CO, NOx emission of the Euro III vehicles, and the effect of the sulfur on emission is generally linear. Also through scientific designed fleet road test and OBD certification test, study and analyze the effect of the different grade gasoline on the vehicle emission durability and OBD system. The fleet road test indicate that on condition of the Euro 3 test oil, most of the sample vehicles can meet the Euro III emission durability requirement, but the emission aging is significant, the DF is obviously over the recommended 1.2. During the emission durability contrast test, the emission of vehicle which use high quality gasoline is significant low, the discrepancy of mean emission for HC and CO is about 40%, for NOx is about 20%. The OBD certification test indicate that on condition of common market gasoline(sulfur content is below. 300ppm, olefin content is below 30%), the effect on the OBD system is gradual, and LEV use some low quality gasoline occasional may not result permanent emission problems; On condition of the Beijing Euro III standard gasoline, the vehicle emission control system and OBD system can work normally. At last, combine with the relevant test...