Actually it's far simpler, just reset the trip odometer at fill up and divide by the number of gallons you put in at the next fill. Mine was just north of 29 mpg with 5000 miles on the odometer.

 

Data point:
I have been averaging 22 or so mpg for the longer term (mostly highway but lots of surface streets, also I'm a lead foot but my wife has been driving).

We took a road trip over 4th of July weekend. It was about 200 miles each way. We had a Cargo box on the roof (normally no rails or box). Average mpg for the trip was 28.6.

My theory is that the turbo design for massive low end torque means massive gas use under acceleration because it spools so readily. I'd love to see a boost gauge to know if I'm getting into positive pressure on the freeway during cruise.

So there's my analysis. Cruise = good mpg. Stoplight dragrace = nope.

 

y8s

I have a boost gauge ... even at 100 mph steady speed I am not in positive boost in my 2012 all4

that said ... at any speed in any gear above 2000 rpm or so, any throttle movement over just a slight movement will get you into positive boost

even on cruise control, a hill will get you into positive boost

 

I'm getting a consistent 32, with a 50/50 split between highway and city driving. I should also mention I like quick starts and stops, thats why I keep buying Mini's.

 

I just ordered a 2015 CMS automatic. Should arrive sometime in late august early September.

I was planning on doing a serious of driving test which will probably take a few months to complete. (Los Angeles area) Thought I would ask if anyone has done the following...

Test mpg with sport only.
Test mpg mid mode.
Test mpg green mode.

I see so many different mpg posts and not all mentioning if they are driving a manual or auto tran. From the info I gathered from this post though is the manual gets significantly better mpg which bums me out considering the auto cost $1250. I would of went manual if my wife new how to drive one but she doesn't so it looks like I'm in for lower mpg.

Anyway, when I get my CMS I will post my findings if they can't be answered here.

 

Our speed limits are very strict in Belgium.I drive mostly on roads where the allowed speed is 44 and 56 miles. Our highways are so crowded that you can never manage to get a decent average speed.
I have a Cooper automatic with a different motor management made in the factory.The power is there with lower rpm.
MPG= 38 -40
Fuel is Total Superplus 98
Oil= castrol titanium 0-30
Tires are=Continental premium Contact 2 in 205/55/17

 

According to Fuelly, After 30 fill-ups I'm getting on average 27.8. Most of that is going to and from work on mostly twisty mountain back roads. My best was 32.7 when I drove out to the airport in Denver twice on one tank which was all highway.

Note: If you want to have fun and get better gas mileage, don't hit the sport button....It seems to cause a prius to pop out in front of you, forcing you to drive too slow to even get the engine warm....sigh.