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I've run across a number of articles about the new 15% Ethanol blended fuel. The EPA says it's OK to put in passenger cars from 2001 and newer. The auto makers (basically all of them) are saying this will damage the car and void the warranty. The auto makers are saying flex-fuel vehicles and most (but not all) 2014 models can handle the new blend.

What say ye?
 

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How big a book do you want me to write?? I researched it several years ago. What I found is for normal use it is a horrible fuel.


E15 is a blend of Gasoline & Grain alcohol. The number tells you the percentage of Alcohol in the mix so this is 15% Alcohol, 85% Gas. Most of what has been available since the 1970's is E7 & E10 (Pumps are often labeled as E10 but are actually have E7 to cut down on problems)

Alcohol is corrosive and attacks some types of rubber and aluminum parts in the fuel system. This was a big problem in the 1970's when it was first mandated into Gas. To strong of a content and it will destroy these parts, unless the fuel system made with alcohol compatible parts. At 10% mixture the effect was considered minimal in the 1970's.

Alcohol has a higher octane value then pump gas. Straight Ethanol has about 100 mon octane rating. It can be used to raise octane in fuels.

Alcohol attracts water. It will draw it out of the air in high humidity environment. When water mixes with it it has the tendency to fall out of the gas mixture. This can cause problems with vehicles that sit alot, and vehicle that change altitude alot. (Airplane fuels are mandated not to have alcohol)

Alcohol's chemical makeup contains an Oxygen molecule in it. It actually brings oxygen to the flame. This is why it is mandated in some cities as an EPA blend. Up to 10 percent most engines can handle. Above 10% it can create a lean mixture and cause cylinder temperatures to rise unless the engine computer is programmed to compensate for it. In a pure Alcohol car you are mixing the fuel at about an 8 to 1 ratio. The computer in our cars try to keep the mixture at 14.7 to 1 for economy for comparison.

Grain Alcohol has about 76,000 btu's per gallon. Gasoline (depending the blend) has between 112,000 to 120,000 btu's per gallon. This equates to a loss of gas mileage when running ethanol compared to pure gasoline. It takes a certain amount of btu's to move your car a certain speed & distance. If your car gets 25 mpg on pump gas then 112,000 btu's will carry your car 25 miles at 60 mph. To get 112,000 on Ethanol it will take about 1.5 gallons of pure ethanol so fuel mileage will go down.
 

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I've run across a number of articles about the new 15% Ethanol blended fuel. The EPA says it's OK to put in passenger cars from 2001 and newer. The auto makers (basically all of them) are saying this will damage the car and void the warranty. The auto makers are saying flex-fuel vehicles and most (but not all) 2014 models can handle the new blend.

What say ye?
It is really going to depend on if the computer has the ability to correct the mixture. If it tries to hold a 14.7 to 1 mixture with 15% alcohol blend, then the engine will run lean and burnt pistons could result. If the O2 sensor is able to detect the extra oxygen and correct the mixture (richen it up a bit), then the car should run it (assuming the fuel system seals and all are compliant). I am not sure if it would set codes however I wonder because computer might see a difference/unusual reading between the MAF and the amount of Oxygen coming from the O2 sensor compared to the normal parameters programed.
 
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