Hey guys and gals. I have an 01 x5 4.4i and I just got a lean fault on the #2 bank, it's not running rough but is consuming slot more fuel, my first guess is the 02 sensor as lean doesn't mean more fuel, unless maybe that code prompts it to default to a rich condition? I had it checked for vacuum leaks at the dealer and they came up with nothing. What's my next step?