I borrowed a friends 2003 A6 Quatttro turbo for a couple of weeks and took several short trips in it. I got about 26-27 MPG at 75 MPH on level roads. I just bought my own 2003 A6 Quattro turbo, with lower mileage (55k vs. 75 k) than my friends, and I am only getting about 21-22 MPG on the same trips, also at 75 MPH.
Other than checking the plugs and air filter, what do you suggest I look at for the cause? The car runs fine by the way, and seems to have plenty of power.
Thanks,
Don