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Built motor PCV woes - Input appreciated... Excessive blowby? Vent to atmosphere PCV?

Quebster

Autocross Newbie
Location
Dallas, Tx
Hey all, if it's not one thing, it's another, amirite!?

Anyone running a vented PCV setup with success? How'd ya do it? Currently I have a Spulen V2 PCV plate, with a VWR catch can. Could I do something like tap the top of the can and attach a breather filter? Then of course, block off the catch can outlet and block off the PCV port to the turbo inlet.



Backstory:
Built the motor about 2 years ago, had a VWR PCV system, all was well until BOSS600 v1 wastegate shit the bed running 35lbs of boost. I had this setup most of the year. Sold that, picked up EFR7163, ported the head, shortly after that the VWR PCV stopped venting crankcase pressure properly. Just seems to have busted. Of course no response from VWR. Several other people I know have had the same issue.

So, I put OEM PCV back on and all is well again, at ~34lbs of boost with EFR, other than the known oil-surge issue at the track, where extremely hard braking/cornering causes oil to get picked up by the PCV and routed through combustion (big plumes of smoke).

After WG issues with EFR all year I swap to DBV2 V2 TBB turbski and we tune it on the streets like normal for a couple weeks, get a pump file going, then E85. All on OEM PCV, all is well, zero issues.

Then comes dyno tune day and track weekend. The night before I swap the Spulen V2 PCV plate onto the motor and route it to my VWR can since I already have it. I swapped plates because I'm going to the track and know the Spulen V2 plate fixes the oil surge issue.

Well, after two pulls on the dyno, lo and behold, my VWR catch can is full of 600+ cc of oil. We drain it, finish dyno tuning and make 524whp on a true heartbreaker mustang dyno, so pretty good. Go straight to the track after for a two-day track event, and find out that the can is getting full after just a couple of laps, meaning the rest of the laps the turbo is just drinking oil. Really bad.

By the way, dyno was at a mere 32lbs of boost thanks to the ported head, and at the track I had it turned down to 26-28lbs of boost. So boost wasn't excessive at all.

So I say "Hey USP your Spulen V2 which I've been recommending to everyone just force fed my turbo liters of oil and destroyed it." To which they say, "no way the PCV plate could do that, most likely you have excessive blowby."

Which brings us to now... I do tend to believe that there really is no way their plate itself could cause what happened, there is no diaphram that can bust, it is all aluminum. But if not the plate, then what? If I have excessive blowby, shouldn't I have other problems? I mean guys we're talking enough blowby to send 600+ CC of oil out of the PCV within a couple of stationary pulls. That would have to be an asinine amount of blowby, right? How tf am I making 524whp on a heartbreaker with that much blowby?

And if I have that much blowby, then shouldn't I have symptoms with the OEM PCV on as well? (I don't)

Is it possible that somehow there is somehow too much vacuum in the line from the can to the turbo inlet, to where it is literally sucking oil out of the head? Just trying to figure out wtf to do while Daniel repairs my turbo. Was thinking of trying a vented system.

Bleh. Sorry for the spiel. Compression and leakdown tests were all good last time I did them a couple of months ago for the record. Obviously will be doing them again once I get the car back together. Really any time I have suspected the issue to be something with the built motor it has been anything but.
 
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DSC808

Autocross Champion
Location
HI State
Car(s)
2016 GTI SE MT
OEM PVC restricts the amount of oil getting in (except during extreme cornering) and aftermarket does not have that restriction, sucking in everything?
Dibs on the LSD.... ?
 

Quebster

Autocross Newbie
Location
Dallas, Tx
OEM PVC restricts the amount of oil getting in (except during extreme cornering) and aftermarket does not have that restriction, sucking in everything?
Dibs on the LSD.... ?

Honestly not sure what you're getting at
 

aaronc7

Autocross Champion
Location
USA
Car(s)
17 S3
I think he might be talking about how the stock pcv has extensive baffling while most aftermarket are just wide open path (or very minimal baffling vs oem). Lot of oil splashing around + decent amount of blowby is a recipe for a lot to get pushed out.

I agree it still seems very strange that you'd see such a difference between the aftermarket and oem pcv plates though...something doesn't seem to add up. Maybe it's possible something happened to the engine right before putting the spulen plate on? I would put the oem pcv plate back on and see how it does just as a confirmation if nothing else. And leakdown/comp test like you mentioned.

When I put in a built motor on my other car I had blowby issues too, maybe just looser motor or still breaking in over time. But I had same issue of filling up a catch can after a couple laps. I did have elevated blowby, but I think the bigger issue in my case was oil control. This is somewhat speculation, but only reasonable explanation was oil was pooling up in the valvecover and blocking the pcv vent basically, then I'd get back on the throttle and the blowby pressure would just push/suck the liquid oil straight out. I overfilled a VTA can at one point and oil started spraying onto the headers, I'm just lucky the car didnt catch on fire.
 

Mosquito

Go Kart Newbie
Location
FL
Been wondering what keeps the valve cover from becoming pressurized in the first place. Is it ALL up to the PCV? I know the PCV vents it, but isn't there something else to keep it from happening in the first place? isn't excessive oil blow by a consequence of excessive pressure that perhaps the PCV is unable to actuate on fast enough? Whether the oil makes it out or not would have to do with baffling right? but the condition would still be elsewhere.

I have a "PCV issue" of my own, perhaps somewhat similar but no oil gets to the intake manifold or TIP, instead of seems to be making its way directly to the cylinders & piston heads internally. Spark plugs aren't wet, but soft misfire codes increased from 5-12 on a regular commute to 40-60 while it happens.

Ran APR ST2 HT FBO for 3+ years on the APR catch can+OEM PCV plate. No issues whatsoever. switched to UM which clearly boosts higher up to (29 psi on IS38 at the moment) and I've started getting oil pushed to the cylinders if I get on/off aggressive boost repeatedly. UM said the OEM PCV has a hard time with excessive boost so I should switch to VWR. I went with Spulen V2 instead which I have yet to install.

During the last 4+ weeks since I went UM, I've tried the 3 version of OEM PCV plates AT (original car PCV) BM (as suggested by VW) and BL (as suggested by Audi). All fixed the problem for days on end until I got aggressively on boost. Once I did it would render that PCV to start working incorrectly. How I knew. Excessive burble off throttle that only got worse, considerable drop in MPG, increased additive LTFT from 6% to 14% and oil in all 4 cylinders. Essentially running richer to compensate for the oil in the cylinders. compression is good and there is no smoke.
 

JerseyDrew77

Autocross Champion
Location
Virginia & NC
Car(s)
2016 TR GTI S 6MT
I've said it a bunch of times before, the OEM PCV plate, no matter what revision you use, can not handle the added pressure/boost levels from a hybrid or any other aftermarket turbo. It appears to start failing around 28 - 29 psi.
 

Diggs24

Autocross Champion
Location
de plains! de plains!
Car(s)
2015 GTI
Been wondering what keeps the valve cover from becoming pressurized in the first place. Is it ALL up to the PCV? I know the PCV vents it, but isn't there something else to keep it from happening in the first place? isn't excessive oil blow by a consequence of excessive pressure that perhaps the PCV is unable to actuate on fast enough? Whether the oil makes it out or not would have to do with baffling right? but the condition would still be elsewhere.

I have a "PCV issue" of my own, perhaps somewhat similar but no oil gets to the intake manifold or TIP, instead of seems to be making its way directly to the cylinders & piston heads internally. Spark plugs aren't wet, but soft misfire codes increased from 5-12 on a regular commute to 40-60 while it happens.

Ran APR ST2 HT FBO for 3+ years on the APR catch can+OEM PCV plate. No issues whatsoever. switched to UM which clearly boosts higher up to (29 psi on IS38 at the moment) and I've started getting oil pushed to the cylinders if I get on/off aggressive boost repeatedly. UM said the OEM PCV has a hard time with excessive boost so I should switch to VWR. I went with Spulen V2 instead which I have yet to install.

During the last 4+ weeks since I went UM, I've tried the 3 version of OEM PCV plates AT (original car PCV) BM (as suggested by VW) and BL (as suggested by Audi). All fixed the problem for days on end until I got aggressively on boost. Once I did it would render that PCV to start working incorrectly. How I knew. Excessive burble off throttle that only got worse, considerable drop in MPG, increased additive LTFT from 6% to 14% and oil in all 4 cylinders. Essentially running richer to compensate for the oil in the cylinders. compression is good and there is no smoke.
Are you unhooking the battery when you swap the pcv?
 

Diggs24

Autocross Champion
Location
de plains! de plains!
Car(s)
2015 GTI
I've said it a bunch of times before, the OEM PCV plate, no matter what revision you use, can not handle the added boost levels from hybrid or any other aftermarket turbos. It appears to start failing around 28 - 29 psi.
Yeah, the BL version didn't do shit for me. Honestly I think it's worse than the OEM one. I never noticed smoke coming off a cloverleaf onramp until after I swapped. Maybe it was there before, but I don't know.......
 

Mosquito

Go Kart Newbie
Location
FL
I've said it a bunch of times before, the OEM PCV plate, no matter what revision you use, can not handle the added pressure/boost levels from a hybrid or any other aftermarket turbo. It appears to start failing around 28 - 29 psi.

When I asked UM, they said. "You have basically two ways to go about resolving this, you can either get a VWR catch can or lower boost. The APR catch can setup doesn't vent correctly" (meaning the OEM PCV plate).
I am running a stock IS38 boosting 29 psi, but I think you are right and UM's response goes hand in hand with your take on it.
 

Mosquito

Go Kart Newbie
Location
FL
Are you unhooking the battery when you swap the pcv?

No I didn't. The UM tune seems to keep the fueling system from being monitored (doesn't pass) which seems to make the adaptation of the LTFTs take a bit longer. Didn't think it was hugely necessary, but a new PCV fixes it almost instantly as MPG, LTFT, misfires and oil basically go back to normal in a matter of minutes. Until You get hard on boost that is. Then it goes to hell all over again. I wonder if the inner flapper gets stuck or misaligned in hard boost/vacuum changes and no longer fully seals, but rather partially does...

I might add that when it happens with any of the OEM PCVs I used and damaged, the car idles on cold start as if the oil cap is slightly pulled off. it has a rather rithmic engine noise as if rpms are going up and down a few hundred and as with a vacuum leak, but very very subtle.
 
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Mosquito

Go Kart Newbie
Location
FL
Yeah, the BL version didn't do shit for me. Honestly I think it's worse than the OEM one. I never noticed smoke coming off a cloverleaf on-ramp until after I swapped. Maybe it was there before, but I don't know.......

My AT PCV worked fine forever, switched to the BM about 2 months before switching APR to UM for the hell of it. no issues there, 3 days into UM it begun to "show" signs like wholly hell this tune uses up gas. Went back to AT while I ordered the BL. AT worked well and BL worked well initially too. I found all to be pretty good, until heavy boost, either way. No smoke. I since destroyed the BL and am back to using the AT driving around in embarrassing fashion while I wait for the Spulen to arrive. Anyhow. I hope that fixes it, but didn't want to take way from OP's issue who is running much more boost.
 

donefor

Go Kart Newbie
Location
usa
Is there a baffle in the "doghouse" on top of the Spulen PCV plate? The VWR plate has one that more or less forces the oil to climb over it before it can flow to the CC. It would probably be an improvement to either design to have the hose fitting on top of the doghouse (exiting vertically) rather than in front...
 
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