EPA proposed E15 rule: comment period extended

Here in Minnesota, we are working toward E20. All I've ever used in my Prius for the past 8.5 years has been E10.

Of course, Minnesota is still pushing research. The source & refinement process had been proceeding well for over a decade before the whole spread to the rest of the country hype. We were the test bed and intended to remain that way for the next few stages.

2013 is when the E20 mandate here begins. Heavy testing of the 20% blend has been underway for awhile already.
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I recall a specific recommendation by Toyota about ethanol blends, but can't remember what the maximum was: 10? 20?

 

There is no recommendation. They simply don't endorse higher than a 10-percent blend. Doing that requires a financial obligation.

Biodiesel is in the same situation. Automakers are only required to support 5-percent, so they don't bother with anything higher. Of course, biodiesel carries contaminants (gyclerin). Ethanol is the exact opposite, being a cleanser instead.
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Sorry, I guess I remembered it incorrectly. I recall something strongly worded, not to use over a certain percentage. Whether it was corporate playing CYA, or a genuine threat of engine damage, I don't know.

 

I believe the issue is damage to the fuel system components (lines, o-rings, etc.) if the fuel system is not designed for the higher percentage of ethanol. My 07 manual says no more than 10% Ethanol.

 

Not anymore.

Concern nowadays is on proper fuel/air mixing and emission control.
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