Looks like
13-54-1-440-102 tube elbow, air intake boot
I needed that part on my 2001 3.0i. It was torn, giving me P0171 and P0174 codes (lean in banks 1 and 2).
Very cheap part.
Anything you can do to reduce the leak while waiting to get the part should help.

BTW, on the fuel filter, those are pretty huge, and a really long service life is not a big surprise.

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2001 X5 3.0i, 203k miles, AT, owned since 2014