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PCV “Blowby” and Oil Surge

krs

Autocross Champion
Location
Reno, NV
Car(s)
MKVIIS R
I'm using the BL revision PCV, and a ECS cc. I have since eliminated any smoking under any condition, and my cc has remained dry.
 

tmw2442

Drag Racing Champion
Location
Approved NPC storage contanier
Car(s)
Mk7 R
I'm using the BL revision PCV, and a ECS cc. I have since eliminated any smoking under any condition, and my cc has remained dry.
Didn't catch it on the first skim of the thread...but some are saying the BL failed or did nothing for them....but my experience(and yours...) is the BL works and BL with a can is extra insurance...

Confirm you guys that the BL failed or didnt work....you bought a genuine part an not the amazon/ebay knock offs for $40-50 bucks floating around?
 

mrmattolsen

Autocross Champion
Location
Jacksonville, FL
Car(s)
2015 GTI DSG
I'm still having great luck with my BMS catch can and the stock PCV. Zero smoking.
 
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scrllock

Autocross Champion
Location
MI
Didn't catch it on the first skim of the thread...but some are saying the BL failed or did nothing for them....but my experience(and yours...) is the BL works and BL with a can is extra insurance...

Confirm you guys that the BL failed or didnt work....you bought a genuine part an not the amazon/ebay knock offs for $40-50 bucks floating around?
My '19 R came from the factory with the BL part. It failed under high boost. A catch can and the BL works for some but it is a wear item regardless.
 

Supermoto

Autocross Champion
Location
San Diego
Car(s)
2019 Autobahn DSG
I was having oil surge when autocrossing. The BL PCV actually made the issue worse in that I got oil surge and LOTS of exhaust soot in daily driving. Something about these 2015's.... Because the BL has worked for later years to stop the surging.
This is slightly off topic, but my 2015 was the sootiest car I've ever driven. I would have the exhaust tips clean and within 2 days of driving they would black. Your comment made me realize that I've only cleaned the tips on my 2019 twice since I bought it a year ago, and even then it wasn't caked on soot like the 2015. Just a bit dirty.
 

mrmattolsen

Autocross Champion
Location
Jacksonville, FL
Car(s)
2015 GTI DSG
This is slightly off topic, but my 2015 was the sootiest car I've ever driven. I would have the exhaust tips clean and within 2 days of driving they would black. Your comment made me realize that I've only cleaned the tips on my 2019 twice since I bought it a year ago, and even then it wasn't caked on soot like the 2015. Just a bit dirty.
Honestly probably the PCV. Seeing variability in the quality of them. My 2015 isn’t too sooty at all except when I had the BL PCV on 🤷‍♂️
 
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Superfreak

Drag Racing Champion
Location
Denver
Car(s)
'15 R, '05 Taco,
Hi,
Do you have an update if the BM revision worked on your car?

Thank you :)
It has worked perfectly except once. While trying to log a full throttle pull, I came up on a bicyclist, so I braked pretty hard from the top of 3rd and gave him room. Well it seemed like it had shifted to 4th just prior to me braking really hard, and I got a huge plume of white smoke. It lasted like 5 seconds, smoked so much and accidentally rolled coal on the cyclist.

Anyway I now have this tiny catch can and it rarely collects anything, maybe a couple mils every couple weeks, so far.

1659741405752.jpeg


I can’t explain why the oil would have gone past the catch can, unless it came from somewhere else?
 

GTIfan99

Autocross Champion
Location
FL
BM or BL And a CC is what you want, but beware, some have had bad new PCV straight from VW.

Matt and I both use the BMS CC. I only get oil in it from autocrossing. Stays dry on the street.
 

GTIfan99

Autocross Champion
Location
FL
If you don't care about emissions, you can get one of the systems that remove the PCV, but I can't imagine those are going to be around much longer with how aggressive the EPA has gotten with enforcement against companies creating emissions defeat devices.
 
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Supermoto

Autocross Champion
Location
San Diego
Car(s)
2019 Autobahn DSG
If you don't care about emissions, you can get one of the systems that remove the PCV, but I can't imagine those are going to be around much longer with how aggressive the EPA has gotten with enforcement against companies creating emissions defeat devices.
Would this stop the oil from going into the intake and causing all the carbon buildup we see on these cars? If so I might actually consider doing this.
 

dtfd

Autocross Champion
Location
Massachusetts
Car(s)
MK7.5 GTI
If you don't care about emissions, you can get one of the systems that remove the PCV, but I can't imagine those are going to be around much longer with how aggressive the EPA has gotten with enforcement against companies creating emissions defeat devices.
Would a PCV block off plate/catch can actually have you fail emissions? It shouldn't throw any codes (as far as I'm aware) and since most states check through OBD2 you'll be okay. Obviously visual is a different story.
 

scrllock

Autocross Champion
Location
MI
Would this stop the oil from going into the intake and causing all the carbon buildup we see on these cars? If so I might actually consider doing this.
It stops oil from going into the intake but carbon buildup is from direct injection. Catch cans do nothing for that, despite what people selling them tell you.
Would a PCV block off plate/catch can actually have you fail emissions? It shouldn't throw any codes (as far as I'm aware) and since most states check through OBD2 you'll be okay. Obviously visual is a different story.
A well-designed PCV baffle plate (they aren't PCV deletes, since they still fulfil the purpose of a PCV--positive crankcase ventilation) shouldn't throw any codes. If you're not venting your catch can to atmosphere, there's not much to feel guilty about emissions-wise either.
 

GTIfan99

Autocross Champion
Location
FL
Would a PCV block off plate/catch can actually have you fail emissions? It shouldn't throw any codes (as far as I'm aware) and since most states check through OBD2 you'll be okay. Obviously visual is a different story.
Most states what care about emissions have some sort of visual.

But even if they don't, this would be considered a emissions defeat and companies are starting to shy away from these type of parts. Opened them up to a $4500 fine per device sold.
 

GTIfan99

Autocross Champion
Location
FL
It stops oil from going into the intake but carbon buildup is from direct injection. Catch cans do nothing for that, despite what people selling them tell you.

A well-designed PCV baffle plate (they aren't PCV deletes, since they still fulfil the purpose of a PCV--positive crankcase ventilation) shouldn't throw any codes. If you're not venting your catch can to atmosphere, there's not much to feel guilty about emissions-wise either.

I disagree that cc do nothing. On the street, I'd agree, but I catch oil in my cc on track and at autocrosses, which would have ended up inceasing buildup.
 

Supermoto

Autocross Champion
Location
San Diego
Car(s)
2019 Autobahn DSG
It stops oil from going into the intake but carbon buildup is from direct injection. Catch cans do nothing for that, despite what people selling them tell you.
So if direct injection cars spray the fuel straight into the cylinder, and the only thing moving through the intake is clean air, where does the carbon come from? I thought it's from the PCV system venting oil and vapors into the intake.
 
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