OK, This is great! I just got back from my 05 Journey (storage lot) and have been trying to ID the same source of noise you guys have been discussing. I saw exactly what Rebelsbeach posted in his picture and I also thought the white nib should have a line on it but could not find anything not connected? After reading all this I suspect that is supposed to be that way? At any rate I found that by turning on the vent fan inside, the pump would stop running?
I am guessing that I have something cracked or detached in the dashboard? I say this because the pump stops running when the fan is on. I also noted that using my finger to plug the white nipple on the pump results in it stopping quickly after being plugged.
So, two questions;
is the nipple supposed to be bare? (mine looks exactly like the picture posted)
Is it reasonable to think the line is disconnected behind the dash because of the relationship between running the fan and the pump stopping?
Finally, while I appreciate any and all help, please do not let my wife know I have any knowledge of vacuums or how they operate!