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2.0t FSI EA113; Proper PCV-to-Crankcase breather tube info....

ROH ECHT

K04 PLAY
Location
PDX OR
Car(s)
2007 MKV GTI
I find having to post this info numerous times. So I will post it here so anyone can just share a link when trying to explain it in the future.

There are two designs and combinations of PCV to rear vent/breather tubes.

↓ The Rear Vent Tube PN: 06F 103 215 B; with a check valve, is to be paired with PCV PN: 06F 129 101 P with no check valve: ↓


vent tube3.jpg



If you have the open rear vent tube PN: 06F 103 213 N with no check valve built into it (shown below)...you should only use the PCV PN: 06F 129 101 R with the built in check-valve.
Also; if you have a recycling catch-can or PCV delete plate, those should also be paired with the open rear vent tube. As those two configurations need no valve in the rear vent tube and should never be closed.

vent tube5.jpg



The two combinations are meant to be paired as such, but the valved rear vent tube will function with either PCV. It will just have a second valve along the recycle route to the turbo inlet.

**Removing the PCV, for a PCV delete or catch-can, eliminates crankcase vacuum. The removal of the "PCV-to-intake manifold" tube does this. 'CRANKCASE VACUUM' improves ring seal and valve stem seal, improves power(yes, crankcase pressure reduces power), and removes and burns vapors more efficiently. Allowing the vapors to linger in the crankcase makes it messier in there. Your engine may experience more oil loss for removing the PCV-to-intake manifold" tube...causing it to smoke more from the exhaust.**
 
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Saki Ashraf

Passed Driver's Ed
Location
Houston
ROH thanks for posting this very useful info.

I installed a recirculating catch can system about 15K miles ago on my 2007 FSI GTI and never checked this rear breather.

Currently in the middle of a K04 upgrade and went to check that rear tube after reading your post. It is a valved tube. How would this affect operation of the PCV system? While removing the turbo I did notice excessive oil on the turbo inlet housing and backside of motor - could this be a result of having a valved rear tube combined with a catch can?

Thanks for any comments/insight.
 

ROH ECHT

K04 PLAY
Location
PDX OR
Car(s)
2007 MKV GTI
The valved rear breather tube(RBT) opens when the there is crankcase pressure. When crankcase pressure is low, the valve in the RBT will not be completely open and allows condensation in the crankcase to take more time to evacuate. The oem PCV is designed to switch vapors, to be recycled, over to the intake manifold for the vacuum at low rpms so to remove them. With the connection to the intake manifold removed for a recycling catch-can or PCV delete, the vapors can linger in the engine much longer. With a PCV delete and the valveless RBT, the turbo inlet will draw the vapors out more efficiently. Plus...you never need to worry about the RBT valve sticking shut.

Years ago...many were simply removing the valve from the RBT to avoid buying another. I believe they would cut the center portion out while leaving the outer ring of plastic. in fact, here is one thread/topic on it; https://www.golfmkv.com/forums/inde...er-tube-check-valve-for-bsh-pcv-revamp.55635/
 
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GIACUser

Master Wallet Mechanic
Location
USA
Car(s)
MK 6 GolfR
I didn't see this post, great post ROH!
 

ROH ECHT

K04 PLAY
Location
PDX OR
Car(s)
2007 MKV GTI
BUMP...hoping it becomes STICKY!
 

ROH ECHT

K04 PLAY
Location
PDX OR
Car(s)
2007 MKV GTI
I edited the pics in an attempt to simplify the first post would be more easily understandable.
Apparently it was still too confusing for some....I hope the changes are helpful.
 
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