My X5 Automatic uses too much gas in city driving

[salenks]

Hello,

I moved to a small city in Europe (50,000 people) and I have a problem where my X5 3.0, 2003, automatic transmission, is using too much gas driving in the city. I mean, the city is very small and has crosswalks about every 100 yards (even that is not enough for people so they still cross the street where there is no crosswalk) so there is a lot of stop and go.
I tried accelerating without going over 3,000 RPM, I tried accelerating using higher RPM, then cruising but I still get get only 11-14 MPG. I replaced oxygen sensors about a week ago and now the car has more power but I didn't see any difference in MPG. I was thinking of replacing MAF but it is too expensive to just try it. Would CRC Mass Airflow Sensor cleaner help?
The reason I am asking here is because there is no good BMW mechanic (especially no BMW service center) in the town (with or without right tools). There is a BMW service center about 180 miles away but I don't know if they would be able to tell me exactly if something is wrong and I know the would charge me a lot (example: 1 oxygen sensor from US internet site = 75$, 1 oxygen sensor here = $ 300).

A friend of mine has 2001, x5 3,0 manual transmission who has at least 50% better MPG results than my automatic and he always drives it at maximum RPM.

If anyone has an idea what could be wrong, please let me know.

Thanks a lot,

Sasa