Originally Posted by Homie J Mack

You were right, my friend. I've been barking up the wrong tree the whole time. Thanks to PTECH's wisdom, I discovered a broken plastic t-fitting on this vacuum line behind the intake and next to the firewall. The small plastic boss feeding the small hose into the PCV hose seems to have snapped off. Realizing that capping the now exposed end of the small-diameter vacuum line makes the separator "rattle" stop, I knew PTECH guided me to the finish line. Sincere thanks. Might never have found it, otherwise...

On to my next conundrum... Anyone know the part number for the offending plastic t-fitting and whether or not there's a brass equivalent available? Also, curiously, what does this particular vacuum circuit do for the health and wellbeing of our beloved P!Gs? It seems the larger diameter hoses on each side of the fitting both turn downwards before they both transform from rubber into steel lines on their way down to their un-seeable connections behind each cylinder head. Like A/C lines...

Thanks again for all the expertise,

Vance (aka newbie in Vegas)

Originally Posted by PTEC

Happy to help. The part number is printed on the line itself. I'm sure if you wanted to you could make something out of brass to replace the plastic T and cobble something together but I wouldn't bother if it were me. I cant make it out exactly but it starts with 948. That line goes down to the oil sumps on either turbocharger. The oil that is fed to lubricate the center section of the turbo collects in a little mini oil sump, the liquid oil is pumped out by the scavenge pump. I've never understood exactly why but Porsche puts a crankcase breather line to this sump as well. This is the case on all turbo models including 911s.