engimuneer

With the vehicles that are already FFVs, we've had great luck advancing the timing another 4 degrees in just the flex fuel spark table for power and fuel mileage. Be sure to stick with one fuel or the other. The algorithm usually only gets halfway to 'knowing' the fuel the first 1-2 tanks, then settles at E70-E75.

The_Engineer

I have been running if for several fill ups now. My scan tool says the ecu is reading about 77% ethanol. I think that is just what the station I get it from is blending it at. It will drop as it gets colder and more gas is mixed in.

JAN67

I'll share my experience with E85. I tried it exclusively for a little over a month. My driving habits are to-from work 5-10 miles per day plus typical running around town. My mileage went from about 24 mpg on gas to about 18 mpg on E85. After about 3 weeks of E85 use, I went to Columbus for the weekend (about 2 1/2 hour drive from home). My highway mileage is typically 30-34 mpg on gas, I was getting maybe 22-24 mpg on E85. It seemed like it was a bigger drop-off on the highway for me. I had another day trip about an hour+ away with similar highway numbers.

I switched back to gasoline for now. The availability of E85 in my area is a bit of a hassle. There are two gas stations that carry it, both about 10 miles away, but at least they are in opposite directions. With gasoline prices hovering just over $2.00/gal right now, not worth it at all. If (when) it shoots up over $3.00, I'll probably go back. I might try it again over the winter to compare to my summer results.