Thanks.
The new O2 sensors were Bosh and the retailer was gracious enough to let me exchange the pre and post sensors in bank 2 under warentee to rule out defective sensors (which they said is VERY uncommon). I then even swaped the pre's once again and have reseated all of them several times.

My idle issue is only felt after warm up. I woke up in the middle of the night last night and realized I did not re-check the O ring on the oil dipstick that was replaced/reseated when I did the CCV kit last weekend. Could be a small vac leak there causing new idle issue??

I did not do a leak down test, I think that means a compression test where you leave the valve connect to see if it leaks down? I have no new oil consumption issues if that's any sign of valve problems.

My fuel rail pressure is consistent at idle with the car running, after shut down and the pump off it drops to zero in about 30-60 seconds.

When I say "smoke test" I am using a harbor freight hand pump, cigar and I blow into the tube for pressure. I have held pressure for about 3 min with my finger on the tube. Then either lifting my finger or lifting the oil fill cap - I get the "puff" of pressure release. I do notice the interior gets a linger of cigar smoke even with the windows and doors all closed.

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2004, X5, 3.0, 202k+