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Sorry this has been a little longer in coming than I planned. It's not quite complete and I will edit more into this post as I go [y]

I wanted to simplify the PCV (positive crankcase ventilation) system on my car. The stock setup works well, but over time the materials used to produce these specially formed pipes breaks down gradually due to oily vapour, heat, manhandling when replacing adjacent parts.. etc etc

So I'm doing this for a variety of reasons:

No oily vapour should re-enter the intake. It'll be caught in the catch can. This should:

Keep boost pipes free from recirculated oil vapour

Octane of the fuel shouldn't be reduced (oil vapour reduces octane apparently)

No need to clean throttle body again

No boost leaks from the stock VW pipework under the manifold. Remember, anything in the inlet is either boost or vacuum. If a vac pipe connected to the manifold has a split, it'll leak both under vacuum and boost conditions and the ECU will need to compensate. If enough compensation has to occur that the ECU thinks it's out of tolerance, you'll see a CEL on the dash

The first thing I did was to remove both engine covers. Under the lower cover I loosened the metal plate which houses the N112, the N249, a checkvalve and a small maze of vac pipes

2 x 10mm bolts holding the SAI (secondary air injection) pump inlet pipe

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then 2 x hex bolts holding the plate to the manifold

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Carefully lift the plate from out of the clip on the side of the dipstick holder. If your dipstick holder's never been replaced it'll be very fragile and it'd be a good idea to replace it now for what it costs (about £5-6)

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Now I started removing all the stock pipework from the top

See right behind the dipstick, there's the first small L section of pipe that leads to the suction jet pump Y piece. This is the pipe in which I've previously inserted a checkvalve, to stop boost before it hits the suction pump

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I removed that, leaving the suction pump end exposed

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Next was the infamous for splitting upper breather, on the passenger side of the rocker cover

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It attaches to the TIP via the 'hockey puck' accumulator valve

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Removed

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Then I disconnected the brake booster line, leading from the suction pump

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and finally I took out the lower breather pipe which is located right on the oil filter housing

You can see it on this picture from above, but unfortunately it's not in focus

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I used a long shafted flathead screwdriver to prise off the C clip that holds it in position

http://i4.photobucket.com/albums/y127/patb303/PCV/IMG_0245.jpg

There's an O ring in there too, careful not to lose it!

Removed

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Now I managed to shimmy all the pipework clear and took this photo. The Upper breather Y pipe and the L piece leading to under the manifold are not attached, as mentioned above, I disconnected before removal

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Yeggers! Look at that sludge that's accumulated [:O] Stuff like this clogs the PCV valve, the suction pump and will make it into your TIP..

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Keep these 2 parts for the new installation

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Now I want to cap the vacuum source under the manifold. It's not going to be used, all the pressure is positive coming from the crankcase and upper breather anyway and it'll be caught in the can. The fumes will also pull via the TIP connection when under acceleration. I used a small length of 3/8" ID pipe with a bolt screwed tightly into it

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I'm also wanting to cap the brake booster line and just use the 1 vac source for brakes. It works on the AGU and ARZ so no reason it shouldn't work on an AUM right? I used a 1/2" piece of nylon rod and a jubilee clip but have since replaced this section of the brake booster line. Picture of revised piece to be edited in later

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New picture to show the new brake booster line. I retained the original check valve as you can see, and it now looks a lot neater

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All that's left to do now is cut new 3/4" or 19mm ID pipes, and connect the catch can between both breathers and the TIP

upper breather---catch can---TIP

lower breather /

The can Saikoimichi Type 951

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The hose I got from Hosequip - I spoke to Josh who really is the most helpful fella in the universe. He sorted out some oil pipe so it shouldn't break down over time with all the vapours. As mentioned it's 3/4" or 19mm inner diameter stuff and I used around 1.5 metres

I connected the upper and lower connections to a T piece, and led this into the inlet of the can (top port)

I then connected the outlet (bottom port) of the can back to the hockey puck valve on the TIP

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What I've done here is replace a system that I'm beginning to realise is slightly different depending on the model year of your car

AGU's and ARZ's seem to have only the one hose from under the manifold, straight down to the PCV valve

AUM's like mine (late 2000, X reg) have the hose, split into a Y 'suction jet pump' VW call it, top half coming up through the inlet manifold and joining onto the brake booster line off the passenger side of the manifold. The bottom split goes to the PCV valve

AUM's are different on the later models, my friend Lee has a Y reg that is different. Ste2 has a 53 reg that's also like this and so does Calimori.

They, like the AGU have the single pipe from inlet manifold to PCV, but an additional vac nipple right next to the PCV vac source, that also splits in the form of a suction pump, one half going to the TIP (presumably for pull under boost) and the other coming up through the manifold runners and into the brake booster line off the passenger side of the manifold

I'm not sure what an AUQ setup's like. I haven't seen one to pay any real attention to so if someone knows please post it here [y]

So far I have emptied out a couple of table spoons worth of oily water, so it does appear to be working. I'm going to pull the inlet pipe off soon though just to check everything's flowing okay, with no sludgy buildup
 

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Thats a great write-up Pat [Y] Really useful pictures too.

Think I'll be giving this a go on my ARZ in the near future.

Do you know if the catch can that forge do is any good?

James
 

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i removed my pcv system 2day.. {agu}

what is the reason on having this on the 1.8t's..

most other cars dont?

i take it, it wont do any harm..?
 

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Thats a great write-up Pat
Really useful pictures too.

Think I'll be giving this a go on my ARZ in the near future.

Do you know if the catch can that forge do is any good?

James
I have been looking at installing a catch can on my AUM. From what i have seen, the forge one, although good quality, only has 14mm inlet and outlet connections. The hose used on the standard PCV system is much larger in diameter. Would VW make them so large if this size was not essential? I would try and keep them a similar size, and the catch can used here has the largest connections that i have seen.
 

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Is it possible to install one of these whilst still leaving the PCV system in use? I was intending to install the can between the 'y' shaped breather and the TIP. Would this work, and be effective? I dont want to remove too many components in case i decide to turn it back to standard when selling.

Also, can anybody tell me what the 'Hockey Puck' PCV valve does? Is it a check valve? How can you check if it is still functional?
 

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u can check pcv valve by blowing down pipe its a one way valve..

u can leave it on when installing catch tank..

ive removed it all cause i wanted to eliminate any crank case gases getting back into the inlet manifold..
 

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Ahh!!! So it is a check valve! Mines kafooked! I could go snorkeling with mine [:D] What stupid money do VW want for one of these then?
 

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Just been checking the net after i made a note of the part number:

06A 129 101 A

It seems like this valve is also refered to as a Pressure Regulator Valve. It has a diagphram that restricts flow when the pressure is low in the tip (i.e. under acceleration). Because of this, im wondering if mine is faulty at all?
 

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when i took mine of it was like small plastic cylinder with a spring goes in and out?

only lets air through on way.
 

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I am getting confused?!?!? Do you mean the same component as me? The 'L' shaped connector, shaped like a hockey puck?
 

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This looks great and is a real help as i will be doing mine very soon.

Where did you get the Can from? Looks nice and oem.

Cheers
 

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BaV, have you ever removed your 'PCV' valve that connects between the tip and the pipe that connects to the 'y' shaped breather? You have an AUM like me. I need to know the characteristics of the valve to know if mine is still functioning?
 

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BaV, have you ever removed your 'PCV' valve that connects between the tip and the pipe that connects to the 'y' shaped breather? You have an AUM like me. I need to know the characteristics of the valve to know if mine is still functioning?
Alright mate that isnt the PCV valve you are talking about. I think you are talking about the big hockey puck looking thing that sits next to your DV on your Tip?

The PCV valve is a small check valve that sits in the maze of vacuum tubes that sit above your oil filter housing.

The Hockey puck looking thing as far as i know is some sort of regulating one way valve. It is designed to slow air down passing through the system.

Hope that helps! Feel free to correct me if i have got anything wrong as i'm not 100% i havent started altering this yet i have just done the N249 for now.
 

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Nice one lads. Ive just recieved my Samco Tip from Pritchi83 on here [:D] Not bad for £60! Cheers for that mate! Now I wanna wait to get my catch can before installing though. Im not sure if i wanna remove the existing PCV system. Pat, have you got any CEL codes appearing since you removed or is this not an issue? I was thinking that i could just install it in series between the 'Hockey Puck' and the 'y' shaped breather? It might not be as effective but it should catch some oil no? Or should i remove the full system?

I'm gettin a CEL now saying N249 Mechanical Malfunction, and SAI Incorrect Flow. I want to find the problem for these codes. I was going to remove the N249 valve and possibly the SAI but does this throw CEL codes anyway? These codes were appearing before my 'y' shaped breather split.
 

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Keep these 2 parts for the new installation



I'm not sure what an AUQ setup's like. I haven't seen one to pay any real attention to so if someone knows please post it here
Pat nice write up [Y]

Now it seems you lost me when it came to reinstalling the above two items back on the car. Do you have any pictures or what was done to refit them?

Also to answer your question on the AUQ engine, from looking at yours and comparing it to mine I would say yes they are very similar.
 
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