mhughett

I wouldn't put a lot of faith in the mileage given by the OBC. It is in Audi's best interest to assure that these devices err on the high side. Both my TT RS and my Q5 TDI are about 10% high when I compare with the actual fill-up calculation. I've also noted that the TDI gas gauge doesn't consistently drop with mileage. On the highway, I've seen 200 miles on the first 1/4 tank, then about 150 more to 1/2, then the last half goes in about 150. This makes you think you're getting much better mileage than you are for the first half tank. Then reality sets in. Don't get me wrong--TDI mileage is still excellent. Just not the eye-popping levels you think when you are looking at the gas gauge and doing math in your head.

Transfer

Yup, too good to be true. I realized the 27.6 was calculated for the return trip only (180 miles, good weather, clear traffic). The other 180 miles on the away trip was horrible wind and rain plus traffic a fair bit of the way. So anyway, actual mpg for the entire 360 mi trip, calculated at the pump, was 23.8 mpg which is still pretty decent IMO. Now I'm just not sure if that 27.6 for the return was accurate or not, but I like to think it was.

mhughett

Here is a perfect example as to why you can't rely on the mileage shown on the computer. My wife drove to Illinois today and filled up after 410 miles. The computer said she got 36.3mpg. However, after filling up, she took 12.7 gallons which calculates to 32.28mpg. Still better than the EPA rating but nowhere near what the computer indicated.

Jay Christianson

Did mountain backroads yesterday for 250 miles and got an average of 22.3 - not too shabby for speeding up mountain passes.

ColdBrew

First two fill ups have averaged (calculating at the pump) 18 MPG with mixed driving. I have not been doing any aggressive driving since I'm waiting to get a 1000 miles on it. Actually my wife has been doing most of the driving.