A clogged PCV valve will not only causes sludge, but the inability to vent those obnoxious gases such as moisture, condensation, blowby, etc. will accelerate the deterioration of your otherwise still lots of life left motor oil.
Think your Volvo has a clogged PCV? Keep reading.
If you choose to ignore it, your engine will start burning oil fairly soon due to oil control ring sticking(jammed) due to decomposed motor oil. Also: most seals, such as cam/crank esp. valve stem seals, the elastomers do not take deteriorated motor oil very well and will become brittle/hardened as the elastomer materials being attacked by these polluted motor oils. As a consequence: your engine will start to burn oil far sooner than expected.
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The only parts you have to buy is the oil trap, there are two versions. The one you need depends on your engine serial # and FCP will ask for that. As for how to service the system, be glad I wrote this generic guide on how to do it. Things may vary a tiny bit based on the year of the car, but it’s basically the same.
Added Diagram:
- Ok, for some reason, Volvo likes to overengineer things and the PCV system is one of those things. Now, what you’ll want to do is look down at the fresh air intake pipe right before the turbo. You should see something like what is in this diagram. Now, unplug all of those lines and check for clogging and clean as necessary. Sometimes, those lines are all that get clogged and you get off easy by only having to clean them out. Usually though, the problem lies deeper.
- So, what you’ll have to do is pull the intake manifold. You have a ’95 model, which does have EGR, and makes the job a big pain in the neck.
- Now, what you’ll want to start with is unhooking the intercooler hose that goes to the throttle body and you’ll also want to loosen the bracket that holds the hard IC piping over the engine. Then there are several other hoses that must be detached from the intake manifold up front on the driver’s side. One of them is the evap valve hose and one is the CBV hose.
- You’ll then want to detach the hose from the Idle Air Control Valve, the silver cylindrical thing up near the manifold. That should cover all hoses that need to be removed.
- Next, you’ll want to unbolt the dipstick tube from the manifold. This one is tough to get to b/c you have to do it from underneath the car using a combination of long ratchet reaches to access it. I believe it’s a 12 mm bolt. You can then just rest the dipstick tube against the fan shroud once loose.
- Now back up top, you need to unhook the throttle linkage from the throttle pulley bracket using needle nose pliers.
- I forgot to mention, you have to take off the plastic throttle cover, which is held in by a torx screw (T25 I believe) to get to the throttle area.
- Alright, now you’ll want to remove the throttle body, which is held in by four 10 mm bolts. If you’re careful, you can re-use the TB (Throttle body) gasket that is already on there. Set the TB on the side.
- Then, you’ll have to undo the EGR bolts. There are two 8 mm bolts holding the EGR diaphragm to the intake manifold. I will warn you now that accessing these things is a big headache, but it can be done.
- Once unbolted, the rest of the EGR assembly will just sit in the engine bay.
Now, to take the intake manifold off: I believe there are seven 10 mm bolts actually holding the manifold into the head. There is also a bracket down below that is tough to see that has to be unbolted as well. You can re-use the manifold gasket if you want. - Once pulled, you’ll see a squarish black box on the passenger side (the rectangular black plastic thing on the driver’s side is the starter). That box is the oil trap and is usually what gets clogged. It is usually replaced with a new part, which costs about $30 at the dealer. You’ll want to remove all hoses going to it and verify that they’re clear by blowing through them.
Added Diagram:
Last Updated on March 5, 2022
