1994 Volvo 850 Anomaly - VVIS, vacuum, EGR, PCV, confused

RockstarEinstein · Post by **RockstarEinstein** » 10 Feb 2016, 18:45

My 1994 volvo 850 has The VVIS system, the egr amd pcv system. I am simply looking for someone who has the same car that can simply show me how these are routed.I have The VVIS solenoid controller on the airbox and ANOTHER one ( mystery controller) on the fan shroud mounting next to the egr controller. Mystery solenoid ran to something on the pcv system and to the vacuum tree.
In picture #1 is vvis solenoid
#2 is same unit mounted above fan shroud

: 1 vvis solenoid # 2 mystery

: 1 vvis solenoid # 2 mystery

: Vvis solenoid/ controller

Post by **erikv11** » 10 Feb 2016, 20:13

Scroll down to the bottom of this post, I think it covers all of those parts but maybe not; how much is still unanswered after scrutinizing the diagram?

https://www.matthewsvolvosite.com/forums ... hp?t=53247

Post by **abscate** » 11 Feb 2016, 06:48

]Reposting diagram....what a Charlie Foxtrot System!

RockstarEinstein · Post by **RockstarEinstein** » 11 Feb 2016, 08:39

I have this diagram, my question, more clearly is there is ANOTHER valve that is run to the vacuum tree AND the second valve in line on the pcv from valve cover . Which is labled in 3 rd pic as "mystery"
I even had Mr. Robert Diy from you tube come to my house amd look at it amd scratch his head amd run off.

RockstarEinstein · Post by **RockstarEinstein** » 11 Feb 2016, 08:41

Does anyone have a diagram or a picture of the pcv valve system or the egr system?

Post by **erikv11** » 11 Feb 2016, 09:50

Are you sure that mystery part isn't a variant on the EGR solenoid, like an aftermarket replacement?

So your car's engine bay contains everything in the diagram, plus this mystery part? If that is really the case, then I would just (simply

) set it up as in the diagram. If that means leaving out the mystery valve, then so be it.

I think there are some good pics of EGR in the classic engine repair/swap threads:
https://www.matthewsvolvosite.com/forums ... =1&t=28973
Volvo 5-cylinder: How to Replace the Head Gasket

Finally, I only mention this because the engine bay seems to be in pieces so this may appeal to you: you may want to seriously consider just getting rid of VVIS and EGR altogether. You will need a newer ECU, like from a 95 or 96, plus the newer intake manifold that goes with it, but it would get rid of a bunch of baggage in the engine bay. Should be pretty easy to find those parts in a junkyard or from someone on here. That's what I did with my 95, so happy to get rid of the EGR, what a PITA that system is.

RockstarEinstein · Post by **RockstarEinstein** » 11 Feb 2016, 17:28

Ok so chexk this out. My vacuum diagram us such as i attached. Second issue i woild love to eliminate the mystery thingy, except there is an electril 2 prong plug identical to the VVIS plug on the air box.
I will ditch stand it and see .. stand by

RockstarEinstein · Post by **RockstarEinstein** » 11 Feb 2016, 17:45

Now if i could figure out where the PURPLE vacuum is supposed to go that would eliminate that Mystery thingy. What is that part called that it connects to in line with the pcv

Post by **erikv11** » 11 Feb 2016, 18:08

That is not an aftermarket part, it clearly says Volvo on it, I am back tracking on my suggestion to get rid of it. I also realized you need a new head to get rid of VVIS, so that was a half-baked suggestion too.

Can you get the part number from the mystery part? I can't quite tell from the pics.

Also, where is the EGR solenoid, do you have the regular, round kind?

Send a PM to Ozark Lee, he has a 94 and can maybe help out here more constructively. Perhaps others can too, but I am never good with the 94 and 93 quirks.

RockstarEinstein · Post by **RockstarEinstein** » 16 Feb 2016, 22:22

Well, after serious mind boggling evenings, i have figured out what was going on. This valve also has.some control over the egr system as well. Now that the car starts, and runs, my second issue it that when i turn on the heater ac control fan switch ( climate control ) the car dies. I sure do want to run it into a large quarry somewhere right now.