[Diyengineer]

Hello, bought a x5 at auction 151,000 miles. Mint shape. Drove it about 5000 miles without issue. Sometimes it runs perfect. Other times it idles super rough once it warms up. One of the consistent codes it throws is the o2 sensors pre cat are backwards. I’ve replaced all 4 with Bosch, and there is literally no way they can be swapped. Anyone have ideas?

Also, to be more specific. I have the 4.4 V8