The ratio of ethanol and gasoline varies by season. In the winter, there's more gasoline. In summer, more ethanol. This is to help cold starting. Here in SoCal, the difference is pretty minor, but I have noticed that I haven't seem to set a "too lean" code in awhile. I'm also regularly mixing in 91 and not doing straight E85 unless I've got a long trip planned. (Remembering that idle seems to be where E85 "struggles" the most, causing the fuel injectors to go over +20% fuel trim) MPGs continue to be crap, albeit slightly more crap when it's a tank of mostly E85.

An oil analysis from Blackstone came back clean, with wear matching other 5VZ-FE samples. I'll do another analysis next oil change, too, and see if there's any changes.

Also, I did pull a spark plug out and checked out the #4 cylinder, because it was in the middle and represented a good blend of heat soak but not hottest coolant, exhausted into the bank where my aftermarket AFR gauge reads from, and was the easiest to reach. I took photos, but they're photos of a screen, since the cheapie unit I have doesn't capture pictures natively. No visible deposits, or the entire thing is coated and looks like a new protective layer has formed; either way, the pictures-of-the-screen pictures aren't great. I'll dig them up and post them if people really want to see what a 200k+ mile piston top looks like.