Gasahol Questions
 

I have noticed something over the last few fills. For the first couple of days after filling, I find that I have more power and get better mileage, and then afterwards power and mileage start to drop off. Today while driving home I was easily able to get 98mpg but on same trip yesterday with the same general conditions had trouble making 92mpg. I also maintained a higher speed today than I was able to maintain yesterday.

I was wondering if maybe the alcohol is evaporating or if the alcohol is absorbing moisture out of the air and causing the loss of power and mileage. Does anyone else have any ideas on what could be happening. The weather here has been in mid 80s to low 90s with high humidity going up to 100% at night when the temps drop and lots of rain for the past few weeks.

E10 is stable for at least a few weeks, and the Insight vigorously captures fuel vapors, so it really shouldn't have anywhere to evaporate to.

But if alcohol DID evaporate out of your gas, you'd be left with a fuel with more kJ per gallon (how's that for mixed units!), so you'd burn less of it.

I'd wager an improvement in your mood not unrelated to getting a 93.5mpg tank improved your perceptions of your car's speed and performance. ;)

I don't think the mood had too much to do with it, When I got this car it was a rolling wreck, maybe a little worse than yours, I Had to put much of the front end back together. I am beginning to wonder if I got everything back together, I didn't have even pictures to work with when getting and putting it back together, If I took some pics of the mess I have under the hood could you take a gander at them and maybe see if something stands out like a sore thumb? I just wonder If something might be allowing moisture to be absorbed into the fuel system.

I'd be happy to take a look at a thread with pics of your Insight's engine bay.

MN Driver looked under my hood at Hybridfest this year and commented how much different than his it looks. I have my plastic engine cover on display in the garage, my air intake is short and hot, and I don't have A/C. So it's relatively very roomy in my engine bay.