Something keeps BEW O2 sensor tripping codes...???

Hi, I replaced my BEW's O2 sensor with a real Bosch one from IDParts about a 2 years ago (10/2017). In January, I had a P2196 Oxygen Sensor "Signal too High (Rich) code. I asked the guys at my auto hobby sensor if anyone ever has successfully resurrected a O2 sensor with brake cleaner. He said "What have you got to lose"? I removed it and sprayed almost a half a can of brake cleaner: at it, in it's many orfices, around it, and at a cat's eyes as he walked by...jk. Seemed to work! That was in January. Now the code came back up, same code.

Something (It couldn't be the 217K miles on the original turbo) is causing it to get all carboned up I think.

What are some of the likely culprits? The car runs good, good turbo boost, no limp mode anymore (VNT vanes were stuck and I gave them some temporary like by exercising the VNT lever), 525 miles per tank city (automatic wagon, that is pretty decent).

I feel the turbo will be next to go at this mileage. There is oil leaving from the boost pipes (or weeping I guess, since it boosts well enough).

Any things to consider? Thanks!

You need a "dog collar bracket" for the intake hose if you don't already have one. I've seen that cause O2 rich faults.

That was my first purchase Kevin (good suggestion though). I see oil spray leaking in the passenger wheel well. It looks like the oring for the pancake pipe, but that shouldn't mean anything for the O2 sensor getting oil/carboned/etc....