Bypassing PCV and routing to exhaust, description (DIY) (long)

[rippie74]

The inner tubes on my EJ PCV fix is looking brand new, it's really clean. When I was having my clutch JR pulled off the throttle body intake pipe & said there was hardly any oil in there. Which = good. I dn't think my car has gunked up valves... I hardly burn any oil between oil changes which is weird because most FSI motors burn alot of oil.

[gearshifter6]

Just sent these questions as a pm to saaber2, but would appreciate it if you guys could chime in as well:

1.) I noticed you spent $80 on your heater hose. When I was shopping, I saw them for around $20. Are there a difference in the quality of hoses? Do you have a link to where you got yours?

2. Do you think the Venturi effect is strong enough to the point where it may possibly suck oil from the block and cause damage in the form of oil starvation under high load conditions?

3. Will connecting the hose to the rear PCV port be just as effective as connecting to the front where you did yours?

4. How is your car running so far?

Thanks in advance......

[Nickwayne]

This is something I am really looking into, awesome write up and great info

[saaber2]

Quote, originally posted by gearshifter6 »

1.) I noticed you spent $80 on your heater hose. When I was shopping, I saw them for around $20. Are there a difference in the quality of hoses? Do you have a link to where you got yours?

It is a high temp silicone heater hose but it is very possible I overpaid for it as it seemed high but I was in a hurry and didn't want to shop around. It wasn't the standard heater hose. I got mine from thrifty auto parts which was just bought out by carquest. I assume it was from old thrifty stock.

Quote, originally posted by gearshifter6 »

2. Do you think the Venturi effect is strong enough to the point where it may possibly suck oil from the block and cause damage in the form of oil starvation under high load conditions?

I have driven 900 miles so far including city, highway, 0-60, 1/4 mile runs and brief 120+mph cruises and oil consumption has been zero on the dipstick. Normally I would have seen a slight drop in 900 miles as I watch it very close. So it appears that oil consumption has decreased. The 5000 mile mark will tell for sure as I normally consume about 1/2 quart in 5000 miles. I will be doing UOAs as well.

Also the Honda-tech guy (see thread link above) ran two nipples into the exhaust as his preferred method so I don't think it is pulling too much vacuum. If I get time I need to hook up a vacuum gauge but I don't see it happening in the near future.

Quote, originally posted by gearshifter6 »

3. Will connecting the hose to the rear PCV port be just as effective as connecting to the front where you did yours?

In terms of the stock pcv, crankcase gasses under vacuum go out the front port (see diagram above). While under boost, as I understand it the check valve makes the gases go out the back. I wanted to keep it simple and evacuate just like stock that is why I went off the pcv. I suppose if you blocked the pcv that would be just like having the check valve closed and gases would run out the back line but I never messed with that.

Quote, originally posted by gearshifter6 »

4. How is your car running so far?

at 900 miles:

a) Overall car is running the best it has since new. Smoothness is much better than before and power is noticeably better than before (noticeable improvement, not big improvement), especially running around town.

b) Mpg went up roughly by 2. I have a highway strip where I have tested mpg using the MFD since the car was new. Highest I have got there before was 34.5. Now it gets 37 at the highest on that strip at that speed. Also city mpg seems to have gone up but I don't track mpg in city. It always seems to get about 21 on MFD and now it is always about 24 or higher. Just an impression on city mpg though and not measured.

c) Small but noticeable increase in power when "pulling" under boost. I don't have access to a dyno so I don't have any measurables. It is definitely noticeable with butt dyno and 0-60 times went down a little.

d) Oil consumption appears to have decreased but really too early to tell on that as 5000 miles would be a good point to measure

e) Only negative is a slight oil smell and residue noticed at tailpipe. Only noticeable if you are into sniffing tailpipes ha ha.

My impression of the pcv problem is that we are fighting pcv-derived problems from the time when the car is new. Kudos to Rl_RS4 who has done so much work to discover and describe this problem in the audi engines. As the vw language above shows, the pcv gunk on the valves causes numerous other problems, misfiring, incomplete combustion, coil packs going bad, dirty fuel injectors, etc. If I were to speculate, I would say it may also contribute to ring deposits and increased fuel dilution/premature oil breakdown. It is all interrelated. The DI engine is extremely efficient and powerful but it depends on precision and a clean engine and this pcv gunk pugging things up has multiple effects.

The Honda tech guy tested numerous crankcase evacuation methods on his turbo engine and found the slashcut to the exhaust to be the most effective. It sure looks like the simplest and most effective to me. It may be enhanced possibly by running two nipples (see honda-tech thread) but I will leave that up to someone else to test as my car is loving life and so am I. Now that i have pcv problem taken care of I am looking forward to finally doing performance mods.

[INYNN]

Quote, originally posted by saaber2 »

Modified by saaber2 at 3:30 PM 5-17-2009

So did I read this correct? If there is never any boost coming in the front PCV the valve will never re-direct the crankcase gasses out the back PCV?

Meaning if I were to do the "cheaper version" of this mod and vent the front PCV simply out a tube and down where it can vent/drip away the pcv would never send anything out the back at all. Thus giving me 100% crankcase ventilation out the front PCV and down my drain tube only using its own positive pressure and no vacuum assistance?

Thanks in advance if anyone can confirm what im asking here.

[INYNN]

Also, because the rear PCV is in front of the turbo... when in boost would the vaccum of the turbo sucking be enough to pull the PCV valve open and try to draw crankcase gasses out the back PCV?

I'm worried because my car is in boost alot more than its in vaccum if you know what I mean and I want to be sure all the crankcase gases and other crap is leaving my motor and nothing is left to gum up my intercooler and valves with oil residue.

[saaber2]

I'm not exactly sure I understand the Q but if you mean will it work without plugging the rear pcv line I would definitely not do that as you don't want any unmetered air coming in. The rear pcv line needs to be plugged. I hope I understood the Q.



Modified by saaber2 at 5:43 PM 5-30-2009

[saaber2]

Quote, originally posted by INYNN »

Thus giving me 100% crankcase ventilation out the front PCV and down my drain tube only using its own positive pressure and no vacuum assistance?

I don't think anyone can definitively answer this Q. Certainly there are products being sold under this premise (i mean that no vacuum assistance is needed) in the form of "race" catch cans. So anyone buying a race catch can setup is assuming vacuum is not needed for proper crankcase evacuation.

I researched the heck out of it and I found no proof that atmospheric pressure is good enough and no proof that it is not good enough. The best analysis I found was from the Honda Tech guy who if you dig on that forum and find the links, measured vacuum under numerous scenarios including atmospheric. He concluded that atmospheric gave good performance as long as there is adequate ventilation. The questions is, is there "adequate" ventilation under a race can or down tube setup for the 2.0 FSI? (Note that he concluded exhaust slaschcut gives "great" performance). Also like i posted above, the BITOG guy zoomzoom is using the "cheaper version" type of solution on an RS4 and he likes it (uses two vent ports, one on each cylinder bank).

One thing I may do in the future is test this by removing the hose from the exhaust nipple. I have been testing the same oil at roughly 2700 and 5100 miles. So if the exhaust nipple used oil analysis (UOA) showed zero difference than the atmospheric version UOA, that would tell us that the oil is not being degraded any faster via inadequate crankcase evacuation. Of course that UOA test would not tell us anything much about any of the possible positive side benefits such as rings possibly sealing better under vacuum but it would tell us about probably the most important factor.

But this is a pretty indirect way to test it. A better way would be to simply test crankcase pressure under multiple loads/speeds etc. under both vacuum assist and no vacuum assist. I wonder if simply installing a really sensitive vacuum gauge in the line coming from the crankcase (as near as possible to the crankcase) would do that? Is there an easier/better way? Dipstick tube? Oil cap? ???


Modified by saaber2 at 5:47 PM 5-30-2009

[INYNN]

Quote, originally posted by saaber2 »

I'm not exactly sure I understand the Q but if you mean will it work without plugging the rear pcv line I would definitely not do that as you don't want any unmetered air coming in. The rear pcv line needs to be plugged. I hope I understood the Q. Modified by saaber2 at 5:43 PM 5-30-2009

What I was looking to do was just leave the Rear PCV alone (hooked up) and just install the atmospheric vent tube just off the front PCV. Do you know what I mean?

[saaber2]

Just want to clarify. I would definitely plug the rear pcv line. There is no reason to leave it unplugged and you don't want unmetered air getting in there.


Modified by saaber2 at 4:50 PM 6-3-2009

[gearshifter6]

If anyone is wondering where to get these parts, here are some links:

Moroso check valve $16.25: http://store.summitracing.com/...97800

Moroso weld-in nipple $8.25: http://store.summitracing.com/...w=sku

High Temp Silicon Heater Hose16mm (5/8") $3.32/ft. : http://boostcontroller.com/ind...3D154

As for the plugs, per saaber, you can get it at any major autoparts store like autozone or kragens.

[VBMike P]

saaber2. There's a good chance I'm going to do this.

[saaber2]

Quote, originally posted by gearshifter6 »

High Temp Silicon Heater Hose16mm (5/8") $3.32/ft. : http://boostcontroller.com/ind...3D154

Wow, that is a great price on the hose and beats the snot out of what I paid!

[NJRoadfan]

Quote, originally posted by b0mb3r »

I understand that, but is the problem with the emissions is because you are venting exhaust gasses without passing through the cat?

Most states now test vehicles '96 and up by just plugging into the OBD-II port and checking if there is any codes. Very few actually test them at the exhaust anymore besides doing a visual check to see if there is a cat converter installed. If this modification doesn't throw a check engine light, you should "pass" any emissions testing without a problem

[D-TechniK]

Like we say in Miami OP has big 'Cojones'

[SuckSquishBangBlow]

I wonder how much of a pain it would be to hook a vacuum gauge to your setup and drive around under varying circumstances, I would love to see what kind of pull you are getting. One problem I might see in the future with this solution is carbon deposits caking up on the venturi, killing the vacuum.

[Runin2Rich4FSi]

I did the easy way: cap off the rear pcv, put the hose back over the plugged rear pcv, then capped the end of the intake mani with the cap from my bsh kit, then put a filter on then of the front pcv.

everything was great at first, didnt see a difference in performance at all. ( I wanted to see if my rear pcv was failing with this test) Went to the gym, then went to get some food and as I was leaving I noticed a bit of smoke from the exhaust, drove off thinking it was because of the cooler temps outside then realized I had very little boost. The car then smoked as I let it idle in my parking spot. I then put everything back to the original setup and still same results, smoking, little to no boost. could be a problem elsewhere.

[acespizee]

Quote, originally posted by Runin2Rich4FSi »

I did the easy way: cap off the rear pcv, put the hose back over the plugged rear pcv, then capped the end of the intake mani with the cap from my bsh kit, then put a filter on then of the front pcv. everything was great at first, didnt see a difference in performance at all. ( I wanted to see if my rear pcv was failing with this test) Went to the gym, then went to get some food and as I was leaving I noticed a bit of smoke from the exhaust, drove off thinking it was because of the cooler temps outside then realized I had very little boost. The car then smoked as I let it idle in my parking spot. I then put everything back to the original setup and still same results, smoking, little to no boost. could be a problem elsewhere.

I use this setup and dont seem to have any probs.

[Runin2Rich4FSi]

Here is the aftermath of doing this on my car. Not saying it will happen with others but I feel that something is wrong somewhere. I must have went through a quart of oil when I drained all my turbo plumbing, DV, DV housing etc.

[rhouse181]

Quote, originally posted by Runin2Rich4FSi »

Here is the aftermath of doing this on my car. Not saying it will happen with others but I feel that something is wrong somewhere. I must have went through a quart of oil when I drained all my turbo plumbing, DV, DV housing etc.

not too concerned with the local ground/surface water i can see haha

what setup did you try that sucked all that oil into your intake path?

[Runin2Rich4FSi]

I used the 3/4 plug at back of the VC. Then I put a cap on the intake manifold from BSH kit. I kept the stock front PCV setup with the DH check valve and put a filter on the end of that pipe.

[saaber2]

Yeah, you definitely did something wrong somewhere. Maybe you had your pcv valve blocked (backwards check valve?/other?)? What is a DH check valve? Does it open without the vacuum from the intake?

I just checked my pipes coming to and from intercooler and there is zero oil there. Also, there is oil on the bypass line to exhaust (as there should be). Oil consumption has been zero in 1200 miles.



Modified by saaber2 at 4:30 PM 6-17-2009

[saaber2]

Just a followup on the Runinrich issue. I speculated on the buildup:flyingmarchmellow thread that his DigitalHippie (DH) check valve was not opening in the way he had it setup vs. before when the vacuum allowed the check valve to open.

If the valve wasn't opening it would shut off all crankcase evacuation which would not be good and would give problems similar to what runinrich had. Arin@APR also noted that the DH check valve may be unreliable on that thread.

From that thread:

"The only thing I can think of is that the DH valve, which operated fine when there is a source of vacuum, didn't work correctly under no vacuum (for example if it's cracking pressure is too high). That would explain it (if I understand correctly how you had it set up).

Basically if the check valve didn't open it would have the same effect as blocking off both the front pcv and rear pcv line, which would cause something like you described. So you might consider leaving off any check valves when you vent it out the back."



Modified by saaber2 at 10:09 AM 6-21-2009

[saaber2]

Just an update regarding running the line to the exhaust out the back of the valve cover as some people posted about instead of from the PCV as shown in the DIY. BSH pointed out on another thread http://forums.vwvortex.com/zer...age=3 that running directly to the exhaust with no vacuum control could cause too much vacuum and could cause oil starvation.

So it is better to run from the stock pcv as shown in the DIY (don't run it out the back) because the pcv valve controls the amount of vacuum just like it does when stock. Using BSH's numbers, on the stock setup the intake pulls around 20 in hg while the exhaust nipple method pulls around 7 in hg. The stock pcv valve limits this pull to an acceptable amount. Additional non-2.0 FSI specific numbers are also on the Honda-Tech thread linked above but take some reading to find.

[VBMike P]

Have you thought about checking to see what kind of vacuum your bypass draws Saaber2?

[saaber2]

I was extremely motivated to get the valve deposits stopped ASAP but now that the problem is fixed I am way, way less motivated to find the right vacuum gauge, set it up, and worst of all try to run the damned tube through the firewall to the cabin. I hate running stuff from the engine to the cabin for some reason as it always seems to take me forever (on other cars I mean). Maybe there is some slick way of doing it for the Mark V?

I do know that it is not pulling too much vacuum because oil consumption has been normal at 4 oz. in 1700 miles which equates to about 12 oz. in 5000 miles if my math is right. Normal for my car is about 1/2 quart per 5000 miles. So PCV is controlling vacuum.

I also know that it is pulling out gases because I looked inside the hose to the exhaust and it has goo droplets in there. Also you can occasionally smell the oil at the exhaust pipe and very rarely see oily residue on the exhaust tips.

I'm too selfish I guess ha ha. I wanted to have the deposits and related problems gone for good and I definitely want to let others know about it but not motivated enough to put a lot of time and expense into it I guess to try to "prove" anything. I hope a tuning company can do that and make an off the shelf version. If an adequate solution existed that treated the problem I would have bought that and not had to do it myself. who knows maybe I'll get a bug to do something along those lines on a weekend.,


Modified by saaber2 at 10:08 PM 7-9-2009

[VBMike P]

I totally understand. I'm currently running this bypass out the back of the valve cover with a BSH stage 1 pcv plate. I first was running a BSH catch can to prevent smoke and then switched to stage 1 to test it out and cause I got a good deal on the plate alone.

I've put 1k miles on this setup so far with no noticeable oil consumption and have atleast 500 more miles before I'm back home and do any work on my car (at girlfriend's grandparents house in Ohio).

I have a vacuum/boost gauge already but can't do anything til around the 20th when I'm back from my trip. Reading what BSH said in another thread got me wondering about how much vacuum this setup is drawing so I was curious if you have checked before I check.

OT It turns out RLI is 45 minutes from where I am in Ohio so I paid them a visit and took a tour of the place. I bought enough oil to hold me over til when I return for Christmas.


Modified by VBMike P at 4:28 PM 7-9-2009

[saaber2]

It sounds like u r venting to atmosphere? If so, no worries about too much vacuum because there is no source of vacuum. Only issues to consider are: 1) do you have a filter to prevent any dust/etc. form getting into the tube/valve cover? 2) do you have any blockages that would prevent it from venting well such as a check valve? This could potentially cause overpressure in crankcase if check valve impeded flow. If no check valve, no worries 3) does the lack of vacuum mean your oil is degrading faster due to inadequate evacuation?

My guess is you probably have the first 2 covered and the third one no one really knows. You bought yourself some darned good insurance though with the RLI oil IMO.

[VBMike P]

No the pcv is rerouted to the exhaust out of the back valve cover port and the stock pcv is replaced with the bsh stage 1 pcv plate.

[saaber2]

Righto, It's probably fine because you aren't using any oil and they were talking about being concerned with 7 in Hg pulled via exhaust at full throttle for the drag cars and having to refill each run (in other words it was pulling lots of oil vs. yours is using none). They said 1 to 3 in Hg is what the catch cans routed to the turbo run. Since your setup doesn't have the vacuum control from the PCV, it might be nice to check the vacuum.

Someone recommended this blood pressure vacuum gauge as a cheap and very sensitive way to measure vacuum. http://www.amazon.com/Labtron-...r=8-2

That gauge measures in mm HG so would have to times by 0.039374 to convert to inches. It maxes out at 300 mm Hg which is about 11 inches Hg (check my math ha ha). Could do a temporary setup by placing tee in the line and running a small hose to this gauge or similar gauge.

I just checked the Honda tech article and for the Honda Turbo he was seeing a max of 2.2 in Hg with the exhaust slashcut. I believe this was with one exhaust nipple. He added a second nipple for more vacuum but he was looking for power gains while we are looking for a depository for pcv goop and enough vacuum for adequate crankcase evacuation.

Who knows, after you hook up the gauge you may discover that you never reach max levels of any concern and it is better to run it that way. It would good info to know what the max is though for a setup that doesn't use the pcv I think.

Edit: Oops, just re-read your post and see that you already have the gauge. Very interested to see what the readings will be. It is more simple to have no pcv and of course less restriction to flow. The gauge readings should tell use how important the pcv vacuum control component is.



Modified by saaber2 at 10:06 PM 7-9-2009

[VBMike P]

Yep already have an AWE boost gauge, I simply just need to find a T to fit the hose and some time to do it.

I also read in the honda-tech thread about the vacuum draw the guy was experiencing and how he added another nipple. I'm not overly concerned since, like you mentioned, I haven't seen oil consumption as of right now but I'm curious now as to about how much vacuum is created. Figured I'd check if you've done it before I went and did it.

On a positive note, I have been satisfied with this setup and the information you've brought forward. It could be a placebo effect but I felt like there may have been an increase in responsiveness from the engine switching from a stage 2 catch can to a stage 1 plate and the PCV bypassed to the exhaust.

My engine mods are: APR stage 1, BSH intake and DV relocate. My car is about to break 20k and I've been running a catch can from 14k to just shy of 19k. I think I'm gonna pull my intake and check my valves when I get home and hopefully get W/M set up by the end of summer. Then I think I should have no worres about my valves developing buildup.

[aeproberts21]

This is great stuff, and now that my warranty is over I might have to give it a try.

[Britishav8tor]

It might be too soon but Sabre can we get an update on your car and how this set up is working. I have been looking into a BSH race but that looks far to messy and why bother when you can feed it down the exhaust and be done with it ? Also, Has any one found that the OEM PCV (the starship enterprise piece) fails ?

[RABIDRABBIT1983]

Quote, originally posted by Britishav8tor »

It might be too soon but Sabre can we get an update on your car and how this set up is working. I have been looking into a BSH race but that looks far to messy and why bother when you can feed it down the exhaust and be done with it ? Also, Has any one found that the OEM PCV (the starship enterprise piece) fails ?

thats the understatement of the year..............the factory PCV get a F --

[Britishav8tor]

ok but saber's whole system relies on the fact that the front (startship enterprise looking piece) works properly otherwise ... its likely to suck oil out of the head. right ??