Need Some Help, Had problem, Found Problem

[icexx99]

Hey guys I just signed up to this forum and would just like to say thank you for everyones hard work, i heave learned a lot about my x5 thanks to these forums and everyone here.

Recently I had a problem with my x5 that i got a few months ago, the Service engine soon light would go on and off every 3 days or so.. 2001 BMW X5 4.4i,
The codes that were pulled, P0171(Lean Bank 1), and misfires P1341, P1345, P1343, P1349..

I'm pretty good with diy repairs and i went out today to overlook the engine and I noticed this on the back left of the engine, the top hose attached to this didnt seem to be the correct size, and the bottom hose it was connected to was broken off.. funny thing is that i dont know what this thing is and where the bottom hose connects to and that it wasnt screwed on just sitting back there.. I notice a loss of power around 4k rpm.. ANY HELP I would like to order the parts to fix as soon as possible.. Thanks

[Nik]

I believe that's an oil separator.