MK7 to MK8 PCV Install How-To, and Amazon/Epman Turbo Inlet Pipe initial review 

Yeah that's one advantage of the Tiguan hose... it isn't so dumb and bulky... haha.

Yeah it kind of sucks, but the hose at least "should" be a one-time purchase. The valve itself is cheap enough I bought an extra just to have a spare at the track in case I ever do encounter any issues.

how’s your car run now with this kit? any problems?

RU-vid really needs a laugh react. Definitely let me know how it goes! I've been testing a few things I'll be going over once a little more detail is gathered, but essentially the Venturi is the only way to go IMO.

I JUST released a new video going over current findings/trends yesterday where that is basically the topic: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-cRznF5fx4rE.html

Check out the latest video as there have been some new/important developments. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-cRznF5fx4rE.html

Thanks! But the PCV is probably not related to your issue.

I have a 2021 S and have this happen sporadically. I’d love to get to the bottom of it. My thought was the diverter valve (wild guess).

@@Florida_Boi_321 I’ve noticed that with a full tank the issue doesn’t happen. Once the gas starts to go down it happens worse and worse.

The MK7 and MK8 valves have a different hose connection at the PCV itself and are not compatible. The MK8 valve itself is only $65, whereas MK7 valves are all $120+. I've torn a bunch of valves down previously... the MK7 valve diaphragms are considerably more flimsy and lack a self-centering peg in the middle that I think makes the MK8 valve more robust for handling the additional vacuum levels. Considering you'd need to hack up a $130 hose to even attempt to fit it to the MK7 valve, I can't imagine it being worth attempting given how inexpensive the MK8 valve itself is. I didn't explicitly say it, but the reinforced diaphragm is called out in the diagram at this timestamp of the original video: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-jYdF-sOLe3I.htmlsi=c1SRZHIlZkD1FCrW&t=409

@@datadrivenmqb ty for the reply! ;)

That valve is not a Venturi valve, but a one way check valve to make sure that you're not sending boost pressure into the fuel tank. Look at the APR PCV video at the 35 sec mark here: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-aeCQuBDEUEs.html Flow should be allowed from the tank into the barb on the plate. That is likely causing some of the running issues, but even with the plate system installed there will be some weird things noticed. There are dozens of tables dedicated to modeling how much crankcase gasses are being ingested at a given time, etc. I noticed the start-stop function got real weird if I enabled it... the car would stumble when starting and not be happy. Back to an OEM PCV and it's fine. Not that that is "necessary"... but there is a LOT more going on in the ECU to make driveability right than people realize.

@@datadrivenmqb thanks for the reply. Ive been digging around alot the last 24 hours. I guess thats a line for gas vapors to run into the system from the tank. It would make no difference. Maybe the part was included by accident.. and i just double checked my system this afternoon. Once i get my cobb accessport later this week i will be able to keep an eye on my air fuel ratio to see whats going on, on that end. By winter i will prob revert back to the old system. I also might order a new 02 sensor aswell and see if it helps any. I have new plugs and new injectors with about 20,000km at best on them. And did a walnut blast in the fall of the intake ports. Im just trying to find actual answers and your the best on this topic online that ive found so far.lol

Nope, hasn't been an issue. Roughly 15k miles on it, with a bunch of track days, etc. Might just be your hose was more old/brittle?

Good catch. Regardless it still seems to be the closest match to an APR TIP, based off the inlet/outlet dimensions, and especially in the way it has the little standoff where it mounts to the turbo. If I ever find someone local with an APR TIP I'll be sure to get them side by side to be 100% sure. Regardless I don't think any TIPs are particularly any better than others (for overall flow). Stock is likely going to be best for the PCV system if not running the Venturi. As far as aftermarket goes, aside from a few weird ones that have a step right before it enters the turbo (CTS V2), I don't think there are any notable differences otherwise.

Any time when trying to solve a problem I’d recommend a leakdown and compression test to verify engine physical health first. The only thing this won’t catch is bad valve seals (which seem to be somewhat common). If they’re OK then it’s likely the MK8 PCV full retrofit could help. If they’re not “that” bad it’s possible a plate may mask the symptoms and “work” until it doesn’t. FWIW I looked at an APR plate and went over some general recommendations here: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-aeCQuBDEUEs.html&si=pnJqTSZnw1cbEzBJ

Shouldn't be a problem. Just make sure stuff isn't rubbing/chafing and I wouldn't lose any sleep over it.

The idea is that you need a source of boost, but not a source of vacuum. So anywhere pre-throttle body should be useable. Technically you could tap the manifold *IF* you install an in-line check valve that only flows under boost, but seals under vacuum. I'd advise against it only because it adds yet one more complex thing. The 034 TMD is by far the "easy button" and what I'd recommend if possible. Otherwise tapping a charge pipe is the way to go IMO. @JordieG8 recently did this and might be able to show you how he did it.

Oh also! At 9:14, removing the tube from the TIP....if you remove the 2 coolant line mount bolts from the engine, you can slip the tube out (with TIP still attached)

I'd make sure the seal didn't get rolled over when installing the PCV valve. Also ensure the N80 valve was installed correctly, nothing cracked on the PCV itself, etc. What is the specific DTC and full description from VCDS/OBD11?

I'm almost positive the 8Y S3 is the same valve as the MK8 Golf R. Details/parts list at www.datadrivenmqb.com/mk8pcv

If it were a stock car then I'd say keep the factory PCV unless/until problems occur. But based on my research, aftermarket turbo inlet pipes essentially break the factory PCV's ability to function - in which case the MK8 full retrofit is indeed beneficial as it provides a vacuum source that aftermarket TIPs lack. Check out this video for more info on that: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Pjcpla__riY.html Just putting the MK8 valve on without the 034 TMD/Venturi is essentially a lateral move and doesn't have any major benefits (aside from the ability to eventually add the additional parts to function correctly). FWIW I ran the VIN of a random 2019 Tiguan, it has the same PCV valve as my 19 GTI had from the factory (BK revision) so I wouldn't expect any issues performing the retrofit.

@@datadrivenmqb Thanks for the quick reply! Based on several of your videos on the subject I has assumed that even if it didn’t help, it certainly wouldn’t hurt to do the update. I have watched the video you linked and I’m hoping you can clarify something. My first thought was of course, “great, that was a waste of $$.” But then as I watched further, and this is where some clarification would help, my understanding was that aftermarket TIPs didn’t really “break the factory PCV” until WOT. Am I misunderstanding what you were saying? I don’t and have no intention of tracking the car, and even though the additional power from the APR tune is really nice, I don’t think I’ve gone much past half throttle running up to highway speeds on an on-ramp. Based on your reply I do plan on ordering all the parts this weekend, but I was thinking of holding off on the muffler delete short term, just to break up the costs a bit(to keep my wife happy). But if you think that even with the moderate way I drive the car I should just bite the bullet and get the muffler delete right away I have no problem doing that too. Thanks again. This is my first VW(spent 35 years as a tech hating these things LOL), but since inheriting the car from my mom who passed in January, I’ve come to love the car and what to keep it for a good long while since it’s got less than 30K on it.

@@datadrivenmqb on a side note, this may be the first legitimate case where a muffler delete actually has any benefit, with the majority just being manufacturer hype.

Aftermarket TIPs do have a noticeable effect on part throttle gentle acceleration (watch from this timestamp for a few min: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Pjcpla__riY.htmlsi=Frz_D3LwisgaXX4g&t=1356 ), though in daily driving use it's not something that will show up with an actual symptom like smoking. Over time, the longer/more frequent positive pressure events on the crankcase might be more potential to cause leaks from places like the timing cover, oil cap, or cam cradle, etc. but that would require some OEM levels of testing to confirm and correlate the cause. People HAVE been throwing aftermarket TIPs on these cars for years now without "problems"... but I do wonder with how frequent that the above mentioned leaks occur on theEA888.3, how many of those people are/were running aftermarket TIPs. You're not in any danger or anything if you DON'T add the muffler delete right away, but I wouldn't bother with the retrofit at all if you have no intentions of ever adding it. Based on the effects I've observed by changing turbo inlet pipes, the stock TIP would be best to put back on until the Venturi is hooked up, but as mentioned above the differences between them crankcase-pressure-wise really won't be able to be noticed by the end user. Power-wise when I was IS20 there was no noticeable difference in power between stock and aftermarket TIPs also FWIW. If it were MY daily driver Tiguan, I'd honestly just leave the stock TIP on and not change anything at all PCV-wise unless there's an actual problem with it. The APR tune is torque-based so no matter what you do to the car intake/exhaust-wise, it's going to make the same amount of power - the aftermarket TIP isn't doing anything except maybe giving you another 2-3% WGDC improvement. And that's really only realized at WOT. I think the MK8 system is a great PCV system, but the honest truth is it isn't necessary in cases like yours and I'd hate to tell you that you "should" spend money on something that won't really return any tangible value. BUT if you're dead set on keeping the TIP, and want to retrofit it just because you like to tinker (which I can totally relate to... if you haven't noticed), then the full retrofit is the way in my personal opinion. Also sorry to hear about your mom 😢

@@JeffSinon that's basically my take as well😆

If someone locally does the full retrofit install, I'll be sure to do so. Thanks!

Yeah, if you use both of the 1/8 npt extensions there's enough clearance.

Depends on your needs/driving. Track and autocross is far more demanding. Few people have actual problems on the street. www.datadrivenmqb.com/mk8pcv

Just unplug the Venturi hose and cap it. If you’re doing a boost leak test you should be doing it after the TIP so the PCV hose won’t be a factor at that point. Just need to cap the boost line. I just slip a bolt in and clamp it when I am testing things in “basic” retrofit form FWIW.

Not sure about 40, but there are several people running 33-36psi on big turbos (though none on track just yet). I've blasted 120psi of shop air through the Venturi several times when bench testing and it hasn't had any issues for what it's worth.

@@datadrivenmqb That's good info, Thank you. I am running 40psi on a large turbo / Built motor.

@@kurtkennedy5370 yeah I'm not sure what the practical limit of a MK8/Venturi PCV setup is on the street, I imagine that limit will be found at the track first. Once so much blowby is being generated that it's moving more volume through the block passage and is taking oil with it is what will be the determining factor. *Generally speaking* built engines will have more blowby and would be more likely to have issues first. I'd be surprised if it's a problem on the street up to 550-600ish hp though.

Yes, @karstgeo7290 has done the full retrofit on my IS38 1.8 Alltrack.

​@@datadrivenmqbthx for the quick reply. Mine has a noticeable increase in knock at the end of a long commute (52 miles one way daily) with normal driving.

It's the hose that comes with the Tiguan hose. www.datadrivenmqb.com/mk8pcv

Ok cool. I ordered all the parts. It’s for my 2015 gti. I’m confused on the bl and ah codes. Hopefully your link for the mk8 valve works for 2015?

@@user-ut1zy2qc7r BL and AH are different revisions of old MK7 PCV valves. Shouldn't be any issues with retrofitting the MK8 parts in the link to a 2015.