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This paper describes Nissan's research and development work on flexible fuel vehicles. Nissan has been engaged in R&D activities for flexible fuel vehicles to examine the possibilities for long-range energy conservation and air quality improvements. The flexible fuel research vehicle described here employs an electrostatic type sensor to measure the methanol concentration in the fuel and the engine system has been designed to burn a wide variety of fuels from M85 to MO (gasoline). Test results obtained with this research vehicle indicate that OMHCE and NOx emissions with M85 are lower than with MO under a fresh catalyst condition. However, by the end of a 50,000 mile durability test, NOx emissions with M85 increase to the same level as with MO. The use of M85 as the fuel results in a pronounced increase in aldehyde emissions compared with MO.

The FFVs under study operates on either M85 or M0 or any mixture of the two. Nissan has been actively conducting reseach and development on flexible fuel vehicles (FFVs) to explore the possibilities for long-range energy conservation and air quality improvement. The engine converted for use in these FFVs is a 1.6 liter, four-cylinder in-line powerplant, with dual overhead camshafts and four valves per cylinder. It employs the Nissan Variable valve timing Control System (NVCS). The fuel sensor for measuring the methanol concentration in the fuel has been improved both in terms of accuracy and durability. This paper describes the engine performance and exhaust emission levels (formaldehydes unburned methanol and HC emissions) obtained with both M85 and M0.

In 1994, the California Air Resources Board implemented low-emission vehicle (LEV) standards with the aim of improving urban air quality. One feature of the LEV standards is the increasingly tighter regulation of non-methane organic gases (NMOG), taking into account ozone formation, in addition to the existing control of non-methane hydrocarbons (NMHC). Hydrocarbons and other organic gases emitted by S.I. engines have been identified as a cause of atmospheric ozone formation. Since the reactivity of each chemical species in exhaust emissions differs, the effect on ozone formation varies depending on the composition of the exhaust gas components. This study examined the effect of different engine types, fuel atomization conditions, turbulence and emission control systems on emission species and specific reactivity. This was done using gas chromatographs and a high-performance liquid chromatograph to analyze exhaust emission species that affect ozone formation.