Bought a 97 850 GLT in Florida and drove it back to Oregon. Was loosing oil and was told the PVC system needen help . Tried to save the mucho dinero and replaced the PVC system with new from FCP Groton and ended up having to replace all vacuum lines as well. Naturally the car did not run but ended up the wires had come off a relay and after spending many hours trying to find the correct diagram got it going again. After all the pain and anguish of this overly complicated simple repair oil vapor is still coming from the dipstick tube at idle when the engine is hot. I have cleaned the valve again at the bottom of the air intake tube twice. I have noticed the hoses on the top of the oil seperator are reversed on my 850 from the picture at VADIS and FCP Groton. The one from the valve cover goes to the inside on mine and the turbo to the middle one. Hate to take the whole mess apart and read on another site that Groton and VADIS are wrong. Anyone have the same problem and found a reason?

 

I can tell you that VADIS is the correct way it is supposed to me routed. If for some reason you did not connect the hoses correctly, it will cause a problem.

One other thing to consider, did you make sure the holes in the engine block were cleaned out before you installed the new oil separator box?

 

+1 on cleaning out the holes in the engine block- they're always plugged, and if you don't, changing the PCV system won't do a lick of good. to clean them, use solvent and a stiff, thin bottle brush. run the engine for a few minutes after putting it all back together, then change the oil/ oil filter with a really good, efficient oil filter, and change it again after 500-1000 miles..