I have an on-going 2-3-1, 2-3-2 CEL and a very rough idle when cold. Idles better warm but not perfectly.

I've replaced the vacuum tree which was worn through, a few rotted elbows and even found some of the rigid plastic vacuum line had disintegrated in places, which I replaced with rubber vacuum hose. Everything was fine, then this latest situation.

Where does the elbow under the intake manifold feed? The elbow is good but I don't know where the other end goes.

Another point, on the air ducting downstream of the MAF, just before the turbo there is what looks like a PCV type valve with a vacuum line coming in from the side. Is this what ends up going to the elbow under the intake manifold, near the PS pump mentioned above?

Back near the turbo, there is a vac line on the WG actuator of course, but in that general area is one more device with a vac line that looks like it goes up to the vac tree near the throttle bellcrank. What is that device? The hose had slipped off off the nipple and I found it had been repaired before by splicing two together. (Had the car since 2000 and it wasn't me!)

Big question is, can anyone point me to a comprehensive 850T vac diagram? That would surely help knock this project out.

Thanks,

Erwin
'95 855T 155k
'94 945T 132k