I too have been contemplating an O2 swap... got a code for pre-cat 1.

Been looking at different options... can't see paying 270$ for BMW parts, when Bosch is literally less than half that per sensor. Denzo seems to be somewhat reputable.. not sure how they would do though.

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Auto Enthusiast. Tech Extraordinaire.

05' Land Rover LR3
06' E53 X5 3.0i
07' X3 3.0si
08' X3 3.0si
17' Interceptor 3.7 AWD Sedan