P2098 code driving me crazy!!!

[eracer61]

Hi All,

I have a '01 X5 3.0 with 145,000 miles. I've had a P2098 (bank 2 post cat too lean) error for about 9 months. I've tried many different things to no avail - also cleared the code many times. so far I've:
- replaced the bank 2 post cat O2 sensor.
- replaced both pre cat O2 sensors.
- swapped the plugs between the two post cat O2 sensors - front to rear, rear to front (if the O2 sensor is throwing this code this should make it think bank 1 is the one that's too lean).
- had my mechanic look for vacuum leaks. He didn't find any.

no change, still reads P2098 bank 2 too lean.

There has been no negative change in performance or fuel mileage over this time. Any thoughts?

FYI, I've searched the forum with no luck.

Thanks,