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Anyone delete the PCV system?

31K views 66 replies 23 participants last post by  Chilled Man 
#1 ·
Anyone with upgraded boost delete your PCV system yet? What did you use to plug the return hole and coolant holes? Also, can I completely ditch the PTC, or will it throw a code if I disconnect it?

Thanks.
 
#2 ·
From the top of my mind, try TRAV_R or Dougy
I think they replaced the stock system with something custom because they were running a custom manifold.

Also remember someone stating that the stock system is adequate for most performance builds.
Replacing it is only worth it when running absolutely crazy outputs and boosts.

But they can tell you
 
#3 ·
This is next on my mod list. I'm deleting because my pcv system is pumping sludge into the inlet neck of my turbo and a delete is significantly cheaper than replacing the system. What's the PTC?
 
#7 ·
"Why" is typically a core component in advice giving
 
#10 · (Edited)
If you plug all the PCV ports/holes, your engine will blow out cam/crank seals/oil dip stick and start to leak oil over all over the place the first time you drive it.

PCV - positive crankcase VENTILATION. Blow-by gas needs somewhere to go, and PCV let the gas escape. https://en.wikipedia.org/wiki/Crankcase_ventilation_system

You never want to delete PCV, you may replace or upgrade.

Venting PCV to atmosphere works for some car, but not others, and it will also make your car reek of exhaust smell, old cars have this setup, call draft tube.
Other people uses oil catch can to separate the oil and air and have to air re-enter to engine.
Some people uses vacuum pump for the PCV system.
Some people uses exhaust vacuum.
Some improve on stock system, like myself. http://forums.swedespeed.com/showthread.php?341385-PCV-shows-symptoms
 
#12 ·
I know what the PCV system does, and I only asked about plugging the return and coolant holes. The ventilation holes I was considering running to an oil catch can and breather filter which I can empty and clean every oil change or even plumb back into the intake post-filter.

My main concerns are 1) cost of the PCV system parts; and 2) labor to install since i don't have any workspace and the side of the road isn't somewhere I can do a job like this. Although replacing or deleting the system might also be unfeasible on the side of the road, but I'm just exploring options.
 
#15 ·
The check valve was supposedly redesigned to not come apart anymore. It has a roll pin pressed in across the end that is trapped when screwed in.
 
#16 ·
coolant you should be able to no problem especially if you are not going to use the stock pcv piping which helps to reduce the moisture with the coolant ruing through it...but unless you planing to run 700-800+ hp i dont see why you would want to bypass the rest...but if you want to see how it works out, way to find out is -

 
#19 ·
If one was to get ride of the pcv system on this vehicle it would first of all dramatically effect the signal from the maf. That is why thy classic code that is stored when a pcv is plugged is ecm-120d maf flow too low. This intern affects the vacuum signal in the intake manifold what happens next is the ecm starts moving the throttle plate to try to achieve the desired vacuum/pressure in the intake manifold. Then you start getting idle problems. Alot of times you only need to clean out the nipple thats on the right side of the intake manifold takes a few hours and almost no parts. So I guess if you wanted to get rid of the pcv system it would require software so the ecm could make decisions based on a whats going on in the intake without a pcv system.
 
#30 ·
I just paid about $12.50 each at a dealership
 
#32 ·
Ok, got parts yesterday to do a PCV service and dove into it this morning. First off, I'd like to publicly maim the engineer that put the PCV banjo bolt on the BOTTOM of the intake manifold RIGHT ON TOP OF THE ALTERNATOR. That bolt alone took me about 15 minutes to dig out and I'm no stranger to hard-to-reach fasteners ...

Secondly, anybody know what this is for?
Obviously it's a sensor for the PCV system but I can't find it in any diagrams in VIDA.

Thirdly, I'm beyond furious that, for a third time now, I've thought I had the smoking gun for my 30 seconds of stumbling idle and MAF code (flow too low) only to take something all the way apart and find nothing wrong with it. I figured this car had never been serviced (PCV) because of all the oil sludge sitting in the inlet neck of the turbo plumbing. The oil trap i removed is oily but clean and the check valve bolt was stamped "2014" ...

I'm starting to pull my hair out with these little issues on my R.
 
#35 ·
If it were up to me, we would have a public hanging and take turns spitting on their bodies; like Musselini.

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Jeeeez...Wow...easy fella...lol...they design things so the stealerships that sell their products can make money labor. :)
 
#36 ·
Also, you only need one of the banjo check valves to service the system. The one on the driver's end of the block is for coolant and can be reused
 
#40 ·
I kept most of the PCV system in place, but simply removed the PTC and connected the output hose to a catch can located in back of the engine compartment. You can either plug the PTC port on the intake to turbo elbow, or replace it with a 90 degree el is which is what I did. No more sludge in the intake pipe and the system works great. Drained a few ounces of oil out of the catch can yesterday that would have otherwise been in the intake.


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#43 ·
I kept most of the PCV system in place, but simply removed the PTC and connected the output hose to a catch can located in back of the engine compartment. You can either plug the PTC port on the intake to turbo elbow, or replace it with a 90 degree el is which is what I did. No more sludge in the intake pipe and the system works great. Drained a few ounces of oil out of the catch can yesterday that would have otherwise been in the intake.

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So, you essentially removed the positive crankcase ventilation and replaced it with a vent to atmosphere...if I follow you correctly. Sounds like what I did on my mustang more or less - although running -12 line from each valve cover to a separate catch can. Common setup in the boosted world.
 
#44 ·
Yep... the plumbing is in tact except that it vents to atmosphere instead of being pulled into the intake. The primary advantage is venting the crankcase under boost through a .50" opening instead of the .080" PTC orifice


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#45 · (Edited)
Yep... the plumbing is in tact except that it vents to atmosphere instead of being pulled into the intake. The primary advantage is venting the crankcase under boost through a .50" opening instead of the .080" PTC orifice

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So unplug ptc and attach a hose to a Catch can and route it back to inlet where ptc would be?

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#47 ·
The vacuum line is needed to create negative crankcase pressure. The catch can is simply in line between the factory oil trap and the intake pipe.


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#53 ·
Neal - are you sure about that? As far as I understand, there's also vacuum (suction) at the inlet to the turbo especially when she's singing. Disconnecting the hose from the inlet means you no longer have this suction. In my case, I spliced in a oil separator/catch can in line with this hose to assist the factory oil separator box.

Guys in the mustang world have debated how to best run the PCV over the years/decades and while there are tons of opinions, they boil down to essentially retaining vs deleting the PCV setup. Deleting means venting the crankcase to atmosphere and plugging any PCV connections to the engine air induction path. Plus side is no worry of pressurizing the crankcase under boost. Downside is no benefit to ring seal without the positive venting of a functional PCV.

On the other hand, running the PCV can be done in such a way that you get the ring seal benefit and do not pressurize the crankcase under load. Volvo seems to have done a decent job of creating a good PCV system. I only added the oil separator/catch can in line in order to help prevent any potential nasties that bypass the factory separator box from getting to the turbo compressor.
 
#54 ·
Neal - are you sure about that? As far as I understand, there's also vacuum (suction) at the inlet to the turbo especially when she's singing. Disconnecting the hose from the inlet means you no longer have this suction. In my case, I spliced in a oil separator/catch can in line with this hose to assist the factory oil separator box.
Hey Andy - the only way you'll have vacuum before the turbo is if your air filter is too small or clogged, otherwise it's air flow, but no restriction to create a vacuum.

My current setup is plumbed back into the intake after a catch can, but I've also run it successfully vented to atmosphere.

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#55 ·
Here's my catch can, ran the oil trap straight to it, then from there to the turbo induction pipe. Was a long task researching Gates molded hoses and waiting for adapters and T fittings to be delivered. I kept the vacuum line to the intake manifold and did a straight coolant line from the thermostat to the head. Now I don't need Volvo's combined pcv/coolant line and it's a more efficient setup. The car was down for a while though but I have a few vehicles.


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#58 ·
Ah, so the check valve is in the banjo connection... makes sense. So, under vacuum, the intake is evacuating the crank case. Under boost, the turbo inlet is evacuating the crank case. Aftermarket catch can still provides function whether the line running to the turbo inlet is vented to atmosphere or going back to turbo inlet.

The factory setup is pretty well thought out and the additional catch can just helps prevent oil getting to the turbo inlet. So, I personally like the factory arrangement with the additional catch can. Although it will still work...I don't see a benefit of venting that line to atmosphere unless the concern is sending oil back to the turbo (but an in line catch can should prevent that). Either way.... :beer:
 
#59 ·
Ah, so the check valve is in the banjo connection... makes sense. So, under vacuum, the intake is evacuating the crank case. Under boost, the turbo inlet is evacuating the crank case. Aftermarket catch can still provides function whether the line running to the turbo inlet is vented to atmosphere or going back to turbo inlet.

The factory setup is pretty well thought out and the additional catch can just helps prevent oil getting to the turbo inlet. So, I personally like the factory arrangement with the additional catch can. Although it will still work...I don't see a benefit of venting that line to atmosphere unless the concern is sending oil back to the turbo (but an in line catch can should prevent that). Either way.... :beer:
[emoji106][emoji481]

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#61 ·
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