[Skywagon]

For what it's worth, and just my opinion. I own an 09 3.5 X6 with about 11k miles on it. I burn Shell 93 Octane exclusively when in my home town and NEVER have any problems. As you all know the federal government mandates gasoline have 10% Ethanol in it, all oil companies are required to fulfill this law. However, I've had the car on two road trips and both times when I left my area and went near large cities I had several "Engine Malfunction" or "Reduced Power" or limp mode occurrences after buying fuels in that area. Restarts always clear the problem.I discussed Ethanol with my local Shell dealer and he stated that some gas station dealers are cheating and buying fuel with higher percentages of Ethanol in it. He cited one dealer he knew of that was caught with 22% Ethanol in his gasoline. Also in my state, if I recall properly, gas stations near larger cities are required by law to have higher percentages of Ethanol for environmental reasons, I think it's 15%. Some claim Ethanol does not burn hot enough and is causing the problem with the turbo chargers thus the "Engine Malfunctions". If I recall this problem may have been discussed at length. However, it seems like more of us are seeing the problem and I'm starting to think it's the gasoline more than the cars.