Another thought I had (lately a lot of "middle of the night thoughts".
I replaced only the pump and reused the sending unit. There is a clear plastic accordion tube from the pump to the cover. I did not see any cracks or holes but I did not test it for pressure. If there was a hole in that tube, YES fuel would leak on the outbound as well, but it would just spray back into
the tank and I think our pumps pump at a greater pressure than required by the fuel rail? So in this theory, I could lose my prime if that tube leaked before The check valve of the pump yet it supplies the required pressure to run the car. But I still think my fuel issue is separate from trim issue.

Am I correct that running "rich" Will prematurely use up the catalytic converters lifespan?

Thanks!

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2004, X5, 3.0, 202k+