First check the fuel delivery. Look for fuel trims. Check them at idle, and then again under load.

If the above checks out I would check that the voltages for the 2 pre-cat O2's are within spec. Especially the one for bank 2 since that's what that P-code is pointing at.

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2005 X5 4.4i Build 04/05 Maintenance/Build Log
Nav, Pano, Sport (Purchased 06/14 w/ 109,000 miles) (Sold 8/15 w/121,000 miles)

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Nav, DSP, Pano, Running Boards, OEM Tow Hitch, Cold Weather Pckg (Purchased 08/15 w/ 90,500 miles)

2010 X5 35d Build 02/10
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