Need Urgent Help..Oil In My Rear Breather Tube..Blue Smoke On Deceleration.

[Mego]

Hi Guys,

i have blue smoke coming from my exhaust when cruising downhill with no gas on pedal,when i reach a stop and then start to move again i can see a puff of blue smoke out of my exhaust,i changed my front pcv and problem still exist,i removed my valve cover and couldn't make sure its cracked,but i saw some oil in my rear pcv(breather tube).
the car is an 2007 gti mkv with stage 2 tune(software+downpipe+intake).
the car runs fine and oil consumption is very good(less than half a quart in 1k mile).
i never see these puffs of smoke before going stage 2 with downpipe fitted since i have been stage 1 + intake for over 2 years but after going stage 2 the problem got started.

Any help would be much appreciated and im ready to answer any questions u ask in order to solve this problem.

Thanks again.

[john87]

When I went on a banger rally earlier this year, one of the cars used to smoke badly on deceleration. It turns out that the turbo 'oil return line' was blocked, therefore oil pressure was building up and forcing its way past the turbo seals. You could be suffering a similar thing, but not necessarily.. since you say oil consumption is very good 

[xjay1337]

I had this on my GTI. Did the same as you, blue smoke on the overrun, usually after hard acceleration.
Caused no issue and no oil usage. Car was on 115k and turbo was very healthy so just ignored it.
I also had cleaned my sump and new pickup pipe etc.

I also only had the issue after fitting a decat.

[scopes]

This might help !

From another site :- But the forum member is on here also, so he could maybe help out with this...

@ROH ECHT

http://www.golfmkv.com/forums/showthread.php?t=188457&page=2
IE replied and I was correct in that I could bypass the evap flow through the v-cover (evap flow is the red line), so:

I put 5/8" (front) and 1/2" (rear) rubber caps over both ports along the red line after disconnecting those two evap hoses in order to eliminate the need for the port where the crack may be causing oil to feed into the turbo inlet resulting in smoke.
Then added a 3/8" coupler to the rear hose. Then added a 3/8 hose that fit onto the front evap hose (over the o-rings) and connecting to the rear barbed coupler...using hose clamps at all connections and bypassing the valve cover altogether...smoke is gone and no need to replace the valve cover unless I want to at some other time. I will get on it, as I usually do, and also keep note of the oil usage over time to see how this performs.

Total cost was under $10





Yes...IE's kit appears to provide an alloy bit that will clip onto the front OE line, but I believe the rear hose needs to be removed and the new line connects to the turbo inlet. ↓
See the connection @ "Evaporative Emission (EVAP) Canister Purge Regulator Valve N80" page 14 and you will see that making a connection there doesn't look like a fun day:
http://www.golfmkv.com/forums/golfgo...golfengine.pdf

I didn't mind clipping the connection clips because If I ever needed...I could easily buy a new OE line for the front. I may remove the front OE EVAP line altogether as there is a barbed fitting at the other end of the front OE line. Then I will add a 3/8" barbed 90deg elbow to the hose in back so I can run my EVAP line along the rail tubes and around the "front/passenger side" of the motor to stealthify the mod more. 

Prospective route:

And true...as GIACUser wrote...you will still need the two cap plugs for the OE v-cover.


I finally got around to installing it this morning. The Integrated Engineering piece snaps right on to the connector on the front of the engine without having to modify. It will indeed allow you to plug it back into the valve cover when/if you need to.

Thanks again to Roh Echt - I took it for a drive this morning and tried to produce the 007 smoke screen but amazingly it was all clean. This is just a preliminary drive and I will report back any changes but so far it is great.

From O'Reillys auto parts got a pack of assorted vacuum caps, the 3/8in brass connector barb and a couple of sizes (both small) hose clamps.
Kit from Integrated Engineering had connector for EVAP line and hose.

Install was easy, did not need to remove anything to get at it. Back hose was too hard to remove so I cut it off.




Hope that could maybe help !

 

[ROH ECHT]

Hi, the EVAP bypass worked for those having a crack in the valve cover route only. I indeed had a cracked valve cover effecting both the EVAP and PCV routes, but after trying the EVAP bypass, and a new valve cover, the smoke persisted as well as greater than 1qt/1000 miles of oil loss. So...probably would've worked for me, but I had compound issues. I additionally had a piston rings stuck in the piston groove causing additional oil introduced into combustion. http://www.golfmkv.com/forums/showpost.php?p=3781278&postcount=231

The place to start would be checking the valve cover...spray a cleaner into each route to see if it seeps out.

If all is good...you may be at the onset of worn valve stem guides and/or seals...or yes, even the turbo seal. If you address the valves...look for dissimilar effects on the bottom side of the head, appearance of oil on one or more cylinders than the others. If you see oil soak as in the pic in the link I provided...you may need to remove and inspect those pistons. Or, replace with a short or long block  My complete valve job and 'piston-bearing' job cost $2700usd.

Again, I suggest:
1) Inspect the valve cover...if you find leakage in the EVAP route only = replace the valve cover or do the EVAP bypass. If you find leakage in the PCV route = replace the valve cover.
2) If this doesn't solve the symptoms = address the valve job when possible. 3)-Additionally at that time...inspect for coloration differences on the bottom of the head, and spark plugs, from cylinder to cylinder to determine if the piston rings are sealing properly.

[Mego]

hi all and thx for ur replies.
i did the evap bypass and still same.i wonder what could be the problem since it came after installing the downpipe,been owning the car since 4 years and never saw any smoke,just after installing the dp :(

[Mego]

i wonder is theres a way to bypass rear breather tube which might be my problem in the valve cover.

[Nickd57]

Maybe only seeing it now as theres nothing there to catch it(if your dp is a decat anyway)?

[scopes]

i wonder is theres a way to bypass rear breather tube which might be my problem in the valve cover.

Rear breather tube, that is attached to the turbo ? Rear PCV ?

If thats what you mean, there is a turbo block of plate that can be got, so would that mean, you could just vent the rear PCV to the atmosphere, instead of the turbo ?

R-Tech also do a kit, pretty much the same idea, their PCV delete kit vents to the atmosphere..

 

[Mego]

i wonder is theres a way to bypass rear breather tube which might be my problem in the valve cover.

Rear breather tube, that is attached to the turbo ? Rear PCV ?

If thats what you mean, there is a turbo block of plate that can be got, so would that mean, you could just vent the rear PCV to the atmosphere, instead of the turbo ?

R-Tech also do a kit, pretty much the same idea, their PCV delete kit vents to the atmosphere..

 

yes thats right,can u get me the link for that kit?

thanks

[ROH ECHT]

I suggest you address the cause rather than choose to avoid...you will have to address this eventually.
It has nothing to do with a DP and has everything to do with oil recirculating through the intake or combustion. It's either a cracked valve cover, worn valve stems and/or seals, or piston rings. The EVAP bypass only fixes this if the route through the valve cover is compromised. A rear PCV bypass and one-way VTA CC fixes this if the inner PCV route is compromised. A new valve cover fixes both and costs less in the end. If the symptoms persist thereafter, you unfortunately need to be prepared to address the head and/or rings.

[Mego]

i hope its not rings since my oil consumption is very good (less than half a quart every 1k mile).
im gonna get a new vc soon and see if it will solve my problem since i did the evap bypass and it didnt work, and since i have oil in my rear breather tube.