Sure looks the part, and I finally located the other end going behind the engine into the transmission tunnel (but didn't see what it connected to).

It's a vent tube alright, but how the heck did it get turned upside down and backwards? without breaking! and where is the "bracket" it attaches to? There seems to be a choice of two, according to Realoem.


I'll find something to attach it to, after I make the opening face down. I'm sure to find more misbegotten malassembled items in my search for the vacuum leak (this isn't it).

And, regarding how to get behind the engine to look for vacuum pieces:
I think I've found it; there are two bolts holding an undertray below the microfilter area. There are angled guides to help slide it back into place (I think). Added 3/25 here's a couple of videos showing how to do it: https://youtu.be/Qxo5tg1qVRc or https://youtu.be/Eq00ZAOwc88 works on both 3.0i and 4.4 engines. I'll try it Monday, after the wife gets home (I limit my undercar activity, and also disabling vehicles, to times when I can get an unwilling assistant, to lend me a hand).

__________________
01 BMW X5 E53,3.0i-5L40E, 7/13/01
topas-blau,Leder-grau,"resto-project car"

Here:
14 Lexus ES350,3.5L-U660E
09 HHR Panel,2.2L-4T45E
04 Chevy 2500HD,6.0L-4L80E
98 GMC Sierra 1500,5.7L-4L60E

Gone:
66 Chevelle Malibu 2dr ht.,327>441c.i.-TH350>PGlide/transbrake
08 Cobalt Coupe,2.2L-4T45E
69 & 75 C10s,350c.i.-TH350
86 S10,2.8L-700R4
73 Volvo 142,2.0L-MT4
72 & 73 VW SuperBeetles,1.6l-MT4
64 VW,1.2l-MT4
67 Dodge Monaco 500 2dr ht.,383c.i.-A727
56 Chevy 210 4dr,265c.i.-PGlide