help with vacuum line?
 

2004, X5, 3.0, M54

does anyone know where the other end of the small vacuum hose that exits the firewall between the heater water hoses should go?
(first photo with pine needle)

Second photo is where I think, maybe, it should go??
photo is looking up from under drivers side, along the engine.
If anyone can ID that part I plugged it into OR what this hose controls - would also be appreciated, the hose had a plastic connector and where I think it may go has a frayed fabric covered line.

THANKS!

Bump to this thread. I know where mine attaches; a nipple on the intake manifold right next to the one for the check valve that comes off the vacuum solenoid (that also connects around the valve cover to the emissions vacuum pump).

But back to this vacuum hose--how do you replace it? Mine has disintegrated. Does it just pull off and on here at the firewall? It feels like it goes some distance through this little port into the firewall, and I am afraid that pulling on it will just leave a bunch on the vacuum port on the firewall that I cannot get off.

To follow up on this in case someone else needs to know, I went ahead and tracked the other side of this to a gland/bulkhead port behind the driver's footwell trim under the center console. That line goes to the cabin air temp sensor. The same type of bulkhead connector is on the engine side.

It does just pull off, but my line decayed to the point of leaving some in the recess between the outer and inner port.