I recently filled up at my local shell station for my weekly run and noticed halfway through the week i was getting 3-4mpg less than I usually run. Checked all air/fuel/oil filters and found nothing wrong. When I went back to the same station I noticed a "10% ethanol" sticker on the pump. thinking that may be my problem, since I have never seen the sticker before I drove down the street to a chevron, checked all the pumps for ethanol notices (there were none) and filled up the tank. My mileage went back up to previous #. Just wondering if anyone has had similar problems or if anyone knows where I can find links to which gas companies put max amounts of corn based ethanol in their gas. To my knowledge (based on pumps around town) Shell has the highest.