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Ethanol is highly refined beverage (grain) alcohol, approximately 200 proof, and can be made from natural products such as corn, sugar, and wheat. Ethanol that is used for fuel has been denatured with hydrocarbon, rendering it unsafe to drink.
Ethanol-blended fuel is a mixture of ethanol and unleaded gasoline. A mixture of 10% ethanol with 90% unleaded gasoline is known as E10 (E for ethanol, and 10 for 10%). Automobiles that normally use unleaded gasoline for fuel can also run using E10 fuel. Another type of ethanol-blended fuel is E85. E85 refers to a mixture of 85% ethanol and 15% unleaded gasoline.
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All Hawaii fueling stations will be required to sell E10 by April 2, 2006. However, as Hawaii fuel distributors transition their facilities to accommodate ethanol-blended fuels, consumers will begin having access to ethanol-blended fuel earlier than this date.
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Yes. Other components of gasoline, such as olefins, can cause deposits that result in fouled fuel injectors. However, since 1985, all ethanol blends and nearly all non-ethanol gasolines contain corrosion inhibitors and detergent additives designed to prevent injector deposits. These detergents have been very effective in alleviating the problem of fouled fuel injectors.
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No, because ethanol burns cooler than gasoline. This is the reason that many high-powered racing engines use pure alcohol for fuel.
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Ethanol is an efficient solvent, and therefore, the use of ethanol-blended fuel may result in loosened contaminants and residues collecting in the fuel filter. The fuel filter may need to be changed following the first full tank of ethanol-blended fuel has been used. After this, the fuel filter's normal maintenance schedule may be followed. This problem is very uncommon, and is likely to happen only in older cars that used leaded gasoline.
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Some mechanics do not have correct information regarding ethanol-blended fuel, and like many people, the only thing they know about gasoline is that some of it is blended with ethanol. Some mechanics will suspect ethanol when there appears to be a fuel-related problem with an engine. One reason for this is that in many states, ethanol is the only gasoline component that requires an identifying label.
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When E10 fuel is contaminated with over 0.5% water, the ethanol and water mixture will separate from the gasoline and fall to the bottom of the gas tank. The fuel system must then be drained and new fuel added. Before using ethanol-blended fuel for the first time in an older small engine, all water should be removed from the tank.
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Changes in Gasoline III - The Auto Technician's Gasoline Quality Guide contains comprehensive informaiton about oxygenated fuels like ethanol. This guide covers topics such as fuel specifications, octane quality and fuel volatility and how they affect vehicle performance, oxygenated and reformulated fuels and more. Click here to download a copy of the guide.