So, as I'm sure we all did, got the TDI for it's gas mileage. I have a 2012 sportwagen 2.0 tdi cr140 with the 6 speed dsg. I made sure the tires were at 35psi as the door placard suggested, run biodiesel mix (all we have here), put diesel kleen with all my fill ups, don't run max ac, don't act like im Jesse from fast and the furious, and try to drive conservatively. Yet my average FE is only 31 mpg mix driving (50/50 highway city) and 36 highway. Is this common with the larger wagon?
If you want to compare to my 2010 JSW DSG TDI
- Run 40 PSI tires
- Drive Solo, make sure car is not full of cargo (weight)
- Assume Temps are warm, in Texas this time of year
- Pick a flat freeway (easy in Texas I gather) on a calm day
- Get on the freeway - set cruise 55 mph no more than 60 mph
- Don't use AC, windows up, but can turn fan and outside vents on full
- Stable on freeway, 55-60mph RESET Trip Computer (hold OK button)
- Drive distance of 20-30 miles and note average miles
- You should see 45-50 mpg on trip meter (assuming trip fuel is accurate, checked against fill-ups in past)
My data point, 2010 JSW TDI DSG, when I do the above I can easily get 50 mpg or more. If you do above and only get say 40 mpg, you may have some issue?
My best two tanks, long road trip, out and back home over 1400 miles, over 700 miles each way. I did each way, 700 miles, on one tank full. Each way, average 50-51 mpg. I did keep speed in the 60 mph range. Used AC sometimes, solo summer time.
If all I do is mostly commute, 11 miles each way, 3 miles surface, 8 miles freeway, a 30/70 mix, I easily get 42-45 mpg tank average, no AC and 60 mph...
When all I did mostly city, and/or drove 70-75 mph, my mileage was down in 36 mpg per tank range.
Without knowing how you drive, speeds, if car full of passengers, your 31 mpg sounds low. I have never got less than 34 mpg, even when I drove mostly city and/or like I stole it with AC on.
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