I am trying to replace a lot of vacuum lines on an 850 Turbo Wagon, 94. There are some oddities that I am wondering about in a picture that I am trying to attach.

In this picture, there is a pretty big vacuum connection down next to the PCV connection (yellow arrow). It looks like nothing's been connected there forever.

Also, there are two connections at the upper end (yellow circle) and the only think I can find that goes there is the middle port on the boost controller. So I still have one left over.

 

Part 2:

In this picture, I have removed the plastic piece off that this stuff is mounted on, so you can see.

I have identified the EGR valve controller (orange circle) but I don't know whether the upper port or lower port goes to the valve, or if that matters.

What is the blue circle? That might be a purge solenoid, but it sure is strange how it's insulated, and for what? It is just flopping around in there, and the hard plastic line coming out of it is mangled up, so it no longer goes anywhere.

There is hard line coming around through here (yellow curve) that I think goes to the car's interior. Is that to move HVAC dampers or what? Just curious.

Thanks for any help. I know these sorts of threads are kind of annoying.

 

The "PVC" is actually under the intake manifold. It is the PTC that is in the intake pipe elbow. It's a bigger line that runs from the PCV to the PTC that I'm guessing you are missing.

The stock rubber lines on a turbo tend to bake and carbon up from the inside out. If you can find and afford it try to use silicone lines. They hold up to the heat much better.

The blend door motors on the Heat/AC are electric or manual. They don't have any that use vacuum. It might be the source for the vacuum/boost gauge.

In the turbo hose vacuum diagram the "blue" hose coming off the boost controller goes to one of the nipples on the intake as it should have a filtered source.

Don't know what the black thing in the circle is but I'm sure someone will jump in.

In the third picture the is a "hose attached to intake" that attaches to the intake PTC valve, lower right of the picture. I think this might be the "big" hose you're missing or fell off and is laying in the darkness

 

BTW ... didn't see a dumb question in there anywhere

 

I agree about the big hose that is missing. I was looking at Matthew's volvo site on rebuilding the PCV system, and you could see how that was hooked up on the end near the turbo. The nipple that doesn't go through the PTC, I am guessing was connected to the vent on the valve cover, straight above. That was hooked up to the sidearm on the PTC on my car.

I am not sure where the other end of that big line is supposed to be, though. Still digging.

I have been googling for vacuum diagrams, and at least I now know in vs. out on the EGR valve controller.

 

The hose from the top center of the valve cover goes down behind the intake manifold to that black PCV box. Then another hose goes from the black PCV box around the engine back to that PTC valve.

 

Thanks again. What does the PTC do? I thought it might switch where the engine is vented to, but that's just a guess.

I have a thrilling announcement to make - I replaced the ECM and the car RUNS! I had never heard it run before. The engine sounds good. Turbo spooled up, no smoking. I'm happy with it. However, the intake piping is going to blow apart everytime I step on it, so I will have to work on that.

I was able to find out the yellow line that is traced in my picture is my vacuum/boost gauge. So I am slowly figuring more stuff out.