How long have you owned?
Idle fluctuation sounds more like a vacuum leak issue.
Check the eccentric shaft sensor connection under the beauty cover for oil.
Swap intake and exhaust solenoids after you clean. If code moves to other bank, replace solenoid.
Inspect solenoid connectors and wiring for damage.
I get this code every 6 months or so. I usually clear. Last time I took X5 out and gave it a good thrashing....several WOT runs with 1-2 and 2-3 shifts over 5K. CEL turned itself off.