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Fuel economy is one of the main drivers of the automotive industry. This subject is becoming more and more important showing a clear upraising relevance tendency. The automotive community is researching and developing many solutions and trending technologies to improve the internal combustion engine, realizing its existence is under risk due to strong greenhouse gas impact. Some innovative technologies focus on the internal combustion engines replacement by other energy conversion systems. Other new technologies improve internal combustion engines efficiency but, in most of the cases, impacts on its costs and consequently on its viability, especially considering the entry level passenger cars. In these applications, the cost impact is hardly acceptable by the customers and this market represents a considerable part of the global automotive industry. Any opportunity to improve the vehicle efficiency with minimum cost is welcome.

The flexible fuel applications in Brazil demanded some local challenges to be implemented and one of the most explored and difficult maneuvers is the cold start with alcohol. The cold start with alcohol is much more difficult than when compared with gasoline. Some cold start assistant systems were developed and the Automatic Start Control (ASC) is one of these technologies. Basically this system controls the engine crank based on objective parameters independently from the driver's sensitivity. Considering the instability and difficulty of an alcohol cold start, this automatic start system avoids some driver variability during cold starts. This paper discusses the advantages of the Automatic Start Control assisting a cold start with alcohol in different temperatures. A comparison between Automatic Start Control and a Conventional Start (CS) is performed focusing the main advantages and disadvantages of each system.

The current stringent emissions regulations can be achieved by automakers applying different technologies. One of these recent technologies is the downstream lambda sensor to control catalytic converter oxygen storage. This lambda sensor is installed after the catalytic converter and its response is the oxygen concentration of exhaust gases after the converter compared to ambient. This oxygen content is correlated to the amount of oxygen stored inside the catalytic converter. The stored oxygen is significantly important for the emissions conversion trade of between hydrocarbons, carbon monoxides and nitrous oxides. The ideal stored oxygen is particular to each application and engine operational condition. Besides, the flexible fuel applications must be optimized to control the oxygen stored in catalytic converter according to the fuel blend in tank.

The automotive electrical fuel pumps for gasoline and alcohol fueled vehicles engines are lubricated by the fuel itself. The new flexible fuel engine technology, specially in Brazil, the fuel pump is designed to be lubricated by gasohol (E22) or strait hydrated ethanol fuel but it is also exposed to the variable gasoline/alcohol blends in the flex-fuel engines. This paper presents the influence of different fuel blends, ethanol and gasohol, to the fuel pump wear and corrosion behaviors. The tested fuel pumps were designed for gasohol only engines. The fuel pumps were tested in a bench device, which simulates the vehicle fuel circuit, using gasohol (E22), hydrated ethanol (E100) or 60 % in volume ethanol-gasoline mixture (E60). The scanning electron microscopy examinations and roughness measurements were performed for tribological analysis of fuel pump gears. The observed wear and/or other deterioration mechanisms were mainly due to the abrasion and corrosion.

Two electrical fuel pumps were performed with different fuels in two different vehicles. The pumps accumulated 60.000 km and 190.000 km in passenger cars. Both vehicles and pumps were designed to operate exclusively with gasohol (E22), one of the pumps was tested with 60% ethanol in volume of gasoline blend (E60) for 60.000 km from June-2001 to February-2004. The other pump was tested with gasohol (E22) for 190.000 km from August 2000 to February-2004. The test conditions represented the actual use of the vehicles. Such test is not common vehicle manufacturers practice application because it requires a considered long period of time for evaluation procedure. This test helps both the analysis of soak time influence and the running time. This paper presents a tribological analysis of the components in order to compare the influence of both fuels on wear mechanisms or other degradation that could be influenced by the non usual E60 fuel.