1994 volvo 850 turbo wagon - vacuum hoses

southofmotown · Post by **southofmotown** » 17 Aug 2015, 19:59

I made a repair to the turbo air intake hose and, when I reassembled everything, I found (2) lines (vacuum lines?) that I could not fasten together. I don't know if they were fastened together when I took them apart. You can see in the pics that they are covered by a foam sleeve. I just left them loose under the foam sleeve. Is that the way they are supposed to connect? Thanks.

Sommerfeldt · Post by **Sommerfeldt** » 18 Aug 2015, 03:19

The big hose in the foam sleeve goes to the top of the PTC, while the small one goes on the side of the PTC w/an elbow.
The one on the wastegate actuator comes from the TCV.

It's a little hard to tell, but I think you may have messed it up a little bit.

If that makes any sense at all...

- S

Post by **alschnertz** » 18 Aug 2015, 04:41

The hoses within the foam sleeve go from the PCV canister under the intake manifold to the PTC on the intake bellows as already described.
What I found on my '95 was that the hoses within the foam had become brittle from age and oil vapors. Mine were broken within the foam sleeve.
Bottom line, the only way to fix them is to replace them entirely from the PCV can to the turbo. You may be able to splice in new pieces, but when I tried that, the hose just continued to break further up the line.

Post by **jreed** » 18 Aug 2015, 04:58

I had the same experience as alschnertz... the lines were brittle and cracked. I gently slipped some large diameter silicone tubing over the broken ends and tightened them with tie-wraps. It is just a temporary repair until I can replace the entire PCV system sometime down the road.

southofmotown · Post by **southofmotown** » 18 Aug 2015, 07:03

Okay, so when you refer to the PCV canister, I assume that is the same as the PCV oil trap? There are (2) plastic hoses under the foam sleeve - one comes from the PCV canister and the other from the Turbo air intake hose. I'll have to recheck, but they both seemed solid and unbroken. It looks like they could be connected with some tubing. So bottom line is that they should not be floating unconnected within the foam sleeve? What are the PTC and TCV? I will try to post more pics if I get a chance to dig into it today. Thanks.

Sommerfeldt · Post by **Sommerfeldt** » 18 Aug 2015, 07:48

Yes to your first question there.

In general, no hoses anywhere should be unconnected...

PTC is the thing that stands up from the air intake hoses, down at the bottom. You see it clearly in the first picture of yours. The TCV is the turbo control valve, which has 3 vacuum hoses attached, and is located next to your air box.

- S

southofmotown · Post by **southofmotown** » 18 Aug 2015, 08:35

Okay...In the attached pic, is the PTC circled in red or blue (or neither)?

Post by **abscate** » 18 Aug 2015, 09:31

That is your turbo wastegate. That hose should trace back to a valve mounted on your air cleaner area with one electrical connection and three hose connections. That hose provides boost air, not vacuum.

Snap a pic of the label under your hood with the vacuum hose diagram and post so we can get you straight.

Sommerfeldt · Post by **Sommerfeldt** » 18 Aug 2015, 09:47

Actually, it's the wastegate actuator.

Here you go:

: DSC04807.JPG (140 KiB) Viewed 1968 times

- S

southofmotown · Post by **southofmotown** » 18 Aug 2015, 09:55

So it isn't hooked up correctly? Here's the diagram.