Understanding the MK7 PCV function, retrofitting the MK8 PCV, and why catch cans are bullshit(IMO)

[tigeo]

Do you have the link to this? I feel like I've seen it in another thread and have since lost it haha.

google: "mk7 revised oil cap" and it will point you to it...you can search this group for the same as well...it's posted.

 

[mrmatto]

How much KR are we talking here? The super high amounts due to oil ingestion or the lower "normal" amounts? I see some KR on track even running a few gallons of E85 but nothing of concern/egregious.

Previously, with the mk7 PCV and a CC, I saw up to -13* KR. That was enough to make the car stumble and go "clack clack clack" like a diesel. This weekend with the mk8 PCV I saw up to -9.4* KR. Definitely better and not enough to make the car sound like a diesel for a second, but I still felt the big drop in power. Some of this knock was happening before I was barely into boost, anywhere between 1-10 psi. IATs were not outrageous (100-105*F). https://datazap.me/u/mrmattolsen/st...cv?log=0&data=9-19-39-40-41-42&zoom=4518-4882

 

[tigeo]

Previously, with the mk7 PCV and a CC, I saw up to -13* KR. That was enough to make the car stumble and go "clack clack clack" like a diesel. This weekend with the mk8 PCV I saw up to -9.4* KR. Definitely better and not enough to make the car sound like a diesel for a second, but I still felt the big drop in power. Some of this knock was happening before I was barely into boost, anywhere between 1-10 psi. IATs were not outrageous (100-105*F). https://datazap.me/u/mrmattolsen/st...cv?log=0&data=9-19-39-40-41-42&zoom=4518-4882

Holy shit man...wow. Yeah, I get the typical 1-3 deg at times KR on track, nothing indicating oil ingestion.

 

[Jachas]

I got an idea, just forget all this nonsense and attach a vacuum pump controlled by a vacuum sensor. Forget about hooking anything up to the intake.

I've definitely considered this...

For GTI's , there is a "possibility" to mount OEM electric vacuum pump from EU-spec DADA/DACA engine (1.5TSI), but maybe some NAR vw like Jetta had one of these?(I just know about 1.5TSI DADA/DACA had these el.pump, later 1.5tsi's, like DPCA was in cars with electronic servo, so no need of vaccum, or, AFAIK used only mecanical vaccum pump.


Pump had number 5Q0612181B (Replaced by 5Q0612181E) and the bracket for pump is 5Q0612391K. Pump is mounted where R's have washer fluid reservoir or TDI have fuel filter, behind right headlight. Pump is juts 2 cables (+ and -) some relay + switch + some piping and connection to PCV to fabricate

 

[ITGUY]

For GTI's , there is a "possibility" to mount OEM electric vacuum pump from EU-spec DADA/DACA engine (1.5TSI), but maybe some NAR vw like Jetta had one of these?(I just know about 1.5TSI DADA/DACA had these el.pump, later 1.5tsi's, like DPCA was in cars with electronic servo, so no need of vaccum, or, AFAIK used only mecanical vaccum pump.


Pump had number 5Q0612181B (Replaced by 5Q0612181E) and the bracket for pump is 5Q0612391K. Pump is mounted where R's have washer fluid reservoir or TDI have fuel filter, behind right headlight. Pump is juts 2 cables (+ and -) some relay + switch + some piping and connection to PCV to fabricate

So this vacuum pump goes where the SAI pumps are put in the US models.

 

[anotero]

I just did a compression test on my 1.8 @97K miles....180 give or take a psi across all 4.

Compression tests can be ambiguous. Wife's 1.8t has oil in cylinder 3 (looks like piston oil rings shot), compression came back 175 across the board.

 

[tigeo]

Compression tests can be ambiguous. Wife's 1.8t has oil in cylinder 3 (looks like piston oil rings shot), compression came back 175 across the board.

It's not the oil from up top from the cam cover leaking in?

 

[iwannagofast]

Hello, I have posted about my issue before, but this might be the best place to ask again since this thread is about crankcase pressure. My car has an issue with oil leaking from my Vortex XL turbo from the V-clamp between the turbine and compressor housing. It has been happening for a year and a half now. From what I can tell, the leak occurs anytime the crankcase pressure becomes atmospheric or positive. The stock MK7 PCV seems to keep the best vacuum on the system while at idle and I get "almost" no leaks. I notice a drip or two at the v-band after driving 1000 miles or so. I'm positive it's coming from the v-band, so you don't need to entertain the idea that it's coming from anywhere else. The problem of course is smokescreens after hard pulls, the OEM PCV doesn't last long (my latest one lasted 2 months), and the drips of oil that make my car smell like burning oil sitting at red lights. I have tried the APR and 034 PCV plates and since they both eliminate the vacuum tube under idle, they both create the oil leak, except it's so bad that the oil drips onto the downpipe, then smokes, and it looks like my car is on fire or overheating. I have recently converted to the MK8 PCV and I have found that it creates more pressure than the MK7, but not as much as the APR or 034 plates. This is also confirmed by the OP's testing in that the stock PCV makes -3inHG and the MK8 makes -1.5inHG. The leak is back with the MK8 (although not as bad as the APR and 034 plates).

I pulled the turbo off a year ago and checked all of the drain lines and the v-band. I have spoken to EQT countless times about this and they claim I have a crankcase issue. I have compression and leak down tested my car and it is perfectly fine on all 4 cylinders, so I don't know what crankcase issue they are speaking of. Currently, I want to pull the turbo and ship it back to EQT for inspection or rebuild.

My question is does that seem reasonable to you that the turbo is the issue? Is there anything I could check first before pulling the turbo OR once I pull it, is there a test I could do to confirm a weak seal? Maybe plug the drain and fill it with oil and see if it leaks? I have had this issue ever since going Vortex XL and never had this issue with the IS20 or IS38.

 

[Klrider44]

Hello, I have posted about my issue before, but this might be the best place to ask again since this thread is about crankcase pressure. My car has an issue with oil leaking from my Vortex XL turbo from the V-clamp between the turbine and compressor housing. It has been happening for a year and a half now. From what I can tell, the leak occurs anytime the crankcase pressure becomes atmospheric or positive. The stock MK7 PCV seems to keep the best vacuum on the system while at idle and I get "almost" no leaks. I notice a drip or two at the v-band after driving 1000 miles or so. I'm positive it's coming from the v-band, so you don't need to entertain the idea that it's coming from anywhere else. The problem of course is smokescreens after hard pulls, the OEM PCV doesn't last long (my latest one lasted 2 months), and the drips of oil that make my car smell like burning oil sitting at red lights. I have tried the APR and 034 PCV plates and since they both eliminate the vacuum tube under idle, they both create the oil leak, except it's so bad that the oil drips onto the downpipe, then smokes, and it looks like my car is on fire or overheating. I have recently converted to the MK8 PCV and I have found that it creates more pressure than the MK7, but not as much as the APR or 034 plates. This is also confirmed by the OP's testing in that the stock PCV makes -3inHG and the MK8 makes -1.5inHG. The leak is back with the MK8 (although not as bad as the APR and 034 plates).

I pulled the turbo off a year ago and checked all of the drain lines and the v-band. I have spoken to EQT countless times about this and they claim I have a crankcase issue. I have compression and leak down tested my car and it is perfectly fine on all 4 cylinders, so I don't know what crankcase issue they are speaking of. Currently, I want to pull the turbo and ship it back to EQT for inspection or rebuild.

My question is does that seem reasonable to you that the turbo is the issue? Is there anything I could check first before pulling the turbo OR once I pull it, is there a test I could do to confirm a weak seal? Maybe plug the drain and fill it with oil and see if it leaks? I have had this issue ever since going Vortex XL and never had this issue with the IS20 or IS38.

Are you consuming oil, if so how much?

 

[DerHase]

Hello, I have posted about my issue before, but this might be the best place to ask again since this thread is about crankcase pressure. My car has an issue with oil leaking from my Vortex XL turbo from the V-clamp between the turbine and compressor housing. It has been happening for a year and a half now. From what I can tell, the leak occurs anytime the crankcase pressure becomes atmospheric or positive. The stock MK7 PCV seems to keep the best vacuum on the system while at idle and I get "almost" no leaks. I notice a drip or two at the v-band after driving 1000 miles or so. I'm positive it's coming from the v-band, so you don't need to entertain the idea that it's coming from anywhere else. The problem of course is smokescreens after hard pulls, the OEM PCV doesn't last long (my latest one lasted 2 months), and the drips of oil that make my car smell like burning oil sitting at red lights. I have tried the APR and 034 PCV plates and since they both eliminate the vacuum tube under idle, they both create the oil leak, except it's so bad that the oil drips onto the downpipe, then smokes, and it looks like my car is on fire or overheating. I have recently converted to the MK8 PCV and I have found that it creates more pressure than the MK7, but not as much as the APR or 034 plates. This is also confirmed by the OP's testing in that the stock PCV makes -3inHG and the MK8 makes -1.5inHG. The leak is back with the MK8 (although not as bad as the APR and 034 plates).

I pulled the turbo off a year ago and checked all of the drain lines and the v-band. I have spoken to EQT countless times about this and they claim I have a crankcase issue. I have compression and leak down tested my car and it is perfectly fine on all 4 cylinders, so I don't know what crankcase issue they are speaking of. Currently, I want to pull the turbo and ship it back to EQT for inspection or rebuild.

My question is does that seem reasonable to you that the turbo is the issue? Is there anything I could check first before pulling the turbo OR once I pull it, is there a test I could do to confirm a weak seal? Maybe plug the drain and fill it with oil and see if it leaks? I have had this issue ever since going Vortex XL and never had this issue with the IS20 or IS38.

It could be valve stem seals allowing boost into the crankcase under load. This would never show up on a compression or leakdown test.

Otherwise it could be a restricted drainback hose causing oil to not evacuate the CHRA fast enough, etc.

FWIW I can't imagine the difference in ~1-1.5inHg of vacuum would change rate of leaking enough to notice from MK7 to 8 valves, vacuum regardless will pull oil in.

If there are any other oil leaks on the engine those are potential spots for a vacuum leak to occur which will hurt any PCVs ability to maintain vacuum.

It's also entirely possible it's just the turbo that has a failed seal. Typically if you're truly pressurizing the crankcase it will show up as leaks from a bunch of other places as well.

You can try doing the "bench test" on the car like I did here in the 2nd half of the video to see if your rate of vacuum loss is similar or if it drops a lot faster:

For that test since the engine isn't running if you just buy the $20 HF vacuum-10psi fuel pressure gauge, you can just use a conical adapter to insert in the dipstick hole for a vacuum reading during this.


You can build an adapter cap like I did plus buy the gauge to at least figure out what's going on for <$60ish including the gauge while actually driving the car also.

 

[anotero]

It's not the oil from up top from the cam cover leaking in?

I am almost 100% certain it's not. Oil was on top of the piston and on the lower portion of the plug that protrudes into the cylinder. Crazy misfires, loss of power, epc, etc. Perfect dry compression test.

 

[Jachas]

So this vacuum pump goes where the SAI pumps are put in the US models.

Absolutely no, SAI pump is around windscreen washer tank in wheel well and it's on left side (driver side). OEM Vaccum pump goes where TDI fuel filter goes (or windscreen washer tank in R's), behind right headlight (passenger side)

Here I marked pump location and hose on 1.5TSI DADA/DACA engine

 

[JerseyDrew77]

Hello, I have posted about my issue before, but this might be the best place to ask again since this thread is about crankcase pressure. My car has an issue with oil leaking from my Vortex XL turbo from the V-clamp between the turbine and compressor housing. It has been happening for a year and a half now. From what I can tell, the leak occurs anytime the crankcase pressure becomes atmospheric or positive. The stock MK7 PCV seems to keep the best vacuum on the system while at idle and I get "almost" no leaks. I notice a drip or two at the v-band after driving 1000 miles or so. I'm positive it's coming from the v-band, so you don't need to entertain the idea that it's coming from anywhere else. The problem of course is smokescreens after hard pulls, the OEM PCV doesn't last long (my latest one lasted 2 months), and the drips of oil that make my car smell like burning oil sitting at red lights. I have tried the APR and 034 PCV plates and since they both eliminate the vacuum tube under idle, they both create the oil leak, except it's so bad that the oil drips onto the downpipe, then smokes, and it looks like my car is on fire or overheating. I have recently converted to the MK8 PCV and I have found that it creates more pressure than the MK7, but not as much as the APR or 034 plates. This is also confirmed by the OP's testing in that the stock PCV makes -3inHG and the MK8 makes -1.5inHG. The leak is back with the MK8 (although not as bad as the APR and 034 plates).

I pulled the turbo off a year ago and checked all of the drain lines and the v-band. I have spoken to EQT countless times about this and they claim I have a crankcase issue. I have compression and leak down tested my car and it is perfectly fine on all 4 cylinders, so I don't know what crankcase issue they are speaking of. Currently, I want to pull the turbo and ship it back to EQT for inspection or rebuild.

My question is does that seem reasonable to you that the turbo is the issue? Is there anything I could check first before pulling the turbo OR once I pull it, is there a test I could do to confirm a weak seal? Maybe plug the drain and fill it with oil and see if it leaks? I have had this issue ever since going Vortex XL and never had this issue with the IS20 or IS38.

Vortex turbos are shit turbos. Replace that with a different brand turbo and problem solved. There should be zero oil leaking from your turbo. If both oil lines are good and installed correctly then it's the turbo, meaning something has failed within the CHRA.

 

[yakboyslim]

If you had crankcase pressure issue big enough to blow a turbo you would have other issues I would think, seems to me the turbo has a problem. Did you come up with the crankcase theory or did EQT?

 

[iwannagofast]

Vortex turbos are shit turbos. Replace that with a different brand turbo and problem solved. There should be zero oil leaking from your turbo. If both oil lines are good and installed correctly then it's the turbo, meanign something has failed within the CHRA.

Are you consuming oil, if so how much?

I'm only consuming the oil that's leaking from the turbo and my engine isn't leaking from anywhere else. Maybe a 1/4qt or less over 3k miles, the level on the dipstick has gone down by about 3mm and that's after messing with my PCV several times. I agree that it would "seem" that something has failed in the cartridge, however, if your turbo can't physically drain the oil, then it's going to leak from the seals.

I might try the tests listed by DerHase, but all that would prove is that my car is behaving the way it should, or like his. I'm really hoping there is just a block in the drain line, that would be best case scenario I suppose. Is there anyway to check if the block is internal to the turbo cartridge? I just want a way to PROVE that the issue is with the turbo.