Pressure regulating valve and one way valve

[A80Avant]

Looking for these 2 parts new if possible

anyone knows a place that can be ordered in?

part numbers:

034129101b
035103245a

[UrS4boy]

Looking for these 2 parts new if possible
anyone knows a place that can be ordered in?
part numbers: 034129101b, 035103245a

If those are the same as the AAN, there are some options in this post. That said, they aren't that expensive and the dealer would be a good place to start.

http://forums.quattroworld.com/s4s6/msgs/22506.phtml

[A80Avant]

yes those are the ones.

the pressure one is stuck open, the other one i didnt check, but last was replaced 2 years ago.

i know i can try the dealers, but i thought of giving it a go here, as there may be online places to get them delivered. (hectic week coming up)

presumably since the PCV valve is open, i am not getting anything through at idling/cruising and all is going to the maf, correct?

[UrS4boy]

...presumably since the PCV valve is open, i am not getting anything through at idling/cruising and all is going to the maf, correct?

The crankcase ventilation system air is added to the turbo inlet air hose AFTER the MAF, not before the MAF, if things are hooked up properly.

[A80Avant]

i am not talking about what is happening to the MAF itself(cause there is no maf now) but i am asking if the pressure regulating valve is stuck OPEN, i presume that under idle/overrun and cruise, since it is supposed to be closed, thus bringing crankcase ventilation to the inlet manifold, if it is stuck open, all the ventilation is going to the airfilter before the turbo(where the MAF used to be), and not in the inlet manifold. Correct?

[UrS4boy]

..., if it is stuck open, all the ventilation is going to the airfilter before the turbo(where the MAF used to be), and not in the inlet manifold. Correct?

I don't think so.

[A80Avant]

i see
so what is the point of this valve then?

is it only for idling and overrun? to keep closed on these 2 conditions and not interfere with them?

[UrS4boy]

i see. so what is the point of this valve then? is it only for idling and overrun? to keep closed on these 2 conditions and not interfere with them?

The engine crankcase creates oil vapours due to the heat in the engine and in the oil. They can not be allowed to build up and leak uncontrolled to the atmosphere (in the "old days", e.g. before around 1962, they did vent to atmosphere, as "blow-by", an oil vapour/smoke). The 20vt engines have a system that draws these vapours into the intake manifold. When the engine is under vacuum, i.e. idling or low load driving, these vapours are drawn through the one way valve into the intake manifold, just underneath the throttle body. However, when the engine is under boost, you don't want to pressurize the crankcase with boost pressure (because it would push oil past the crank seals). As a result, the one-way valve (ball-type check valve) closes. At that point, the pressure control valve opens under the vacuum caused by air going past the connection to the turbo to intercooler hose, drawing vapours into the intake hoses (all downstream of the MAF). As a result, the crankcase oil vapours still get to the intake manifold, just through a different pathway.

If there is an issue with the pressure control valve stuck open, then oil vapours will be drawn into the turbon to intercooler hose all the time. This will result in build up of condensed oil vapours in the intercooler and/or the Michelin Man hose. Oil in the intercooler will decrease the heat transfer efficiency and oil in the MM hose will cause it to rot and split.

HTH

[A80Avant]

i see
i dont have half the stuff that you describe anyway as the setup has changed over time and upgrades, but best descibe them in a way that others understand as well.

here is a point though. From the housing that the pressure regulating valve is mounted there are 2 metal hoses. One which is 19mm and the other which is 13mm. The 19mm one goes to the MAF route and also serves to house the one way return valve.

The smaller of the 2 metal hoses(13mm) is connected directly to the cyl head (at the back).

In which direction are the vapours running through that smaller metal hose? Are they running from the cyl head to the oil pan/block , OR the opposite?

[A80Avant]

On the above link and ETKA, you can see item 1 or 1A going from the area that connects to the block, up to the cyl head. This metal tube is 13mm and is not regulated by the pressure ragulating valve.

Does anyone know the direction of the blowby from this tube?Is it from the cyl head to the block? or from the block to the cyl.head?

It is likely to be No2, correct? What does is the role of this second tube and why is it bypassed by both of the above valves?

[UrS4boy]

On the above link and ETKA, you can see item 1 or 1A going from the area that connects to the block, up to the cyl head. This metal tube is 13mm and is not regulated by the pressure ragulating valve.Does anyone know the direction of the blowby from this tube?Is it from the cyl head to the block? or from the block to the cyl.head? It is likely to be No2, correct? What does is the role of this second tube and why is it bypassed by both of the above valves?

The cam cover ventilation is drawn into the same path as the crankcase ventilation system. Hopefully, this newly labeled diagram will help?:

[A80Avant]

that clears things up for me! thanks

[UrS4boy]

that clears things up for me! thanks

ναι ! Yay!

[A80Avant]

is that out of translation? or can you do more words than that? haha cool though!