Ok, I would like to know just what effects bad and good that ethanol has on BMW engines. Of course I'm more interested in the M52 engine that I have in my '97 328i, but I'm sure that I'm not the only one who would be interested to know. I of course lost a little gas mileage when I upgraded from factory 15" wheels to 17" BBS RK's, but it really took a hit when all gas stations in the state of Maryland started selling gas w/ 10% ethanol. I typically fill up at the half tank unless I'm on a long drive when I fill up at the quarter tank. Before ethanol I would get a little more than 200 miles before my gas tank was down to 1/2. Now, however, I'm doing good if I get 150 miles before I get to 1/2 tank. If my gas mileage has suffered this much just what is this awful stuff doing to my engine. I keep up on my maintenance. Get my oil changed religiously, the biannual coolant flush, and a carbon cleaning from time to time. So, if someone has access to a good report on just what this stuff does to your engine, I'd be very interested in reading it.