This morning I was getting irritated getting 'only' 32 MPG.

It was 15'F outside, but I did use the block heater this A.M.
What gives?! I was thinking to myself.

Oh ya.... I forgot I was using ( appox. ) 35% ethanol this week.
Until I get my graduated cylinders and pipets, I can't be sure on the %.

I did notice on "Long term fuel trim" with a ScanGauge, I was running with fuel trim at +8.5. Normally with plain gas, this number hovers about zero.

I'm not sure if that number really equals 8.5% more fuel, or if it is just some number. Ideas?

With gas, the number will be negative a few (%?) when coasting, and positive a few (%?) when accelerating, with the median about zero. With 30% ethanol and greater, this number hovers about 8.5, and goes to 12.x when accelerating, and down to 3.x when coasting.

-John

P.S. The mechanics handbook says -20 to +20 are normal values with regular gas. I wonder if that is some limit, or if +25 is possible?
The lowest I've ever noticed was -10 and greatest was +15.