Re: White Smoke after 87 OCTANE??
My Audis also call for premium and I drove my 2003 A6 2.7T for 200k miles (it has 236k now) on midrange and it runs fine. Does not burn a drop of oil and still moves out when I jump on the throttle. The German cars will adjust the timing for lower octane gas at the expense of performance, but 89 should not hurt it. I would not drop down to 87. Generally I alternate 1/2 tanks of midrange and premium. It used to be a 10 cent per grade jump from 87 to 89 to 91. Now the bastiche charge 20 cents per jump in grade. PS - I also did gas mileage tests on long trips using midrange vs premium and could not distringuish between the two. Now, having said that, I also acknowledge that I only drive 10-12k a year now instead of 35k+ and I have started to use premium almost exclusively in both Crossies and my 011 A4 2.oT.