Dec 5 2006
The more general problem is that in the presence of any water the ethanol forms a cloudy water laden mixture which clogs filters, gums up injector, ruins fuel injector pumps or just causes the engine(s) to quit. The initial problem is caused by the MTBE gasoline (old gas) reacting with the ethanol laden fuel (new gas) in the presence of water. Water is the critical reactant. Even after the owner has run all the old gas through we found that the ethanol fuel was more sensitive to any sort of water contamination. It has been reported that when the new E-10 fuel becomes saturated with water it will undergo phase separation. When the water separates from the fuel it takes some of the octane booster with it. E-10 fuel that is saturated drops from 89 octane to 81-82 octane. Now you have both a water problem and low power fuel.