2.0 tsi pcv suction from tiny hole

[kton200281]

Hi everyone 

 

please could someone with a vrs 2.0 tsi see if when they put their finger on the small hole at the side Of the pcv valve whether they feel any slight suction?

 

Am hunting a lumpy idle when hot, and can feel some suction when I do this and then read somewhere this could be the issue, but as There are revisions of this valve unsure if this is meant to be this way? 

 

Thanks and and merry Christmas to all briskodians 

[TheClient]

There shouldn't be suction. It should oscillate in and out I think. If you put a torn piece of paper against it should flap ever so slightly.  Yours may have a failed diaphragm I guess.  I can check my car tomorrow but I am 99% sure. 

[kton200281]

1 hour ago, TheClient said:

There shouldn't be suction. It should oscillate in and out I think. If you put a torn piece of paper against it should flap ever so slightly.  Yours may have a failed diaphragm I guess.  I can check my car tomorrow but I am 99% sure. 

Thank you, appreciate it. Please let me know and I’ll also see if mine does ossicilate 

[TheClient]

This was in some links and technical info @rayx sent me.

 

 

 

Edited 17 December, 2017 by TheClient

[kton200281]

Thanks, just checked it again and I was wrong it just expels air like a mini exhaust. Back to the drawing board re the occasional lumpy idle!

[TheClient]

15 hours ago, kton200281 said:

Thanks, just checked it again and I was wrong it just expels air like a mini exhaust. Back to the drawing board re the occasional lumpy idle!

 

Checked operation of mine at idle.

 

Mine is not like the video. Mine tends to ever so slightly oscillate back and forth, which is what I would think with a diaphragm moving back and forth.  If I press the paper against the little hole it does sort of stick there suggesting the slightest hint of some suction as well.

 

All this assumes mine is good. It is 6 years old and I've been thinking of replacing it to see if it stops the appearance of oil at the end of the intact tract....There is a lot of ways for it to fail and some versions employ a number of check valves as well.

 

@rayx sent me some detailed diagrams of the designs as there are two main design variants on the vRS CCZA and different part numbers which depends on age of vehicle...

[kton200281]

Thanks for checking yours. I have no idea to be honest what is normal on these valves and what isn't - there are various posts on the interweb, someone stating it should expel air only, others suggesting that suggests a fault. The only real way to check the diaphram would be to open the top of the unit and take it out, but it looks like that will result in breaking it in the process. 

 

 

[TheClient]

If there was a fault with the main diaphragm, putting your finger over the tiny hole would likely alter idle / engine splutter etc. I would of thought.  There   is quite a bit more to the part than just the main diaphragm, I was surprised.

[kton200281]

Surely putting your finger over the end would definitely affect the idle? As the vent must serve a purpose and by blocking it off it would affect the idle? 

[Breezy_Pete]

No. The vent is just for pressure equalization as the diaphragm changes position. 

[kton200281]

24 minutes ago, Wino said:

No. The vent is just for pressure equalization as the diaphragm changes position. 

 

Would you not be stopping the diaphragm from moving by putting finger over the end thus impacting the idle?

[Breezy_Pete]

It doesn't need to move at any steady-state operating point.

Edited 18 December, 2017 by Wino

[rayx]

Hope this can help to all Audi/VW SSP Nr. 384, 401 and 436 give official info, below some bonus from internet

 

PCV/Separator version 06H103495E, AC or AH from 1.8 TSI and first 2.0 TSI

 

 

updated PCV/Separator version 06H103495H, AD or AJ from 2.0 TSI only with additional valve sucking gases from under the head cover

 

 

Eighth minute, very informative video

 

 

and few others

 

 

 

[kton200281]

Many thanks for this. I am still none the wiser as to whether the small hole at the side should be emiting air, sucking in air, or both! 

Edited 19 December, 2017 by kton200281

[rayx]

Are the videos and schemas not clear enough? No sucking, no blowing, that hole only allows to equalize the pressure. So that might "pulse", but no permanent blowing or sucking allowed, that points at the problem on the main diagraphm = it´is rupted/cracked.

 

If you block that hole on idling engine, it must not react at all, if it does, diagraphm is KO.

Edited 19 December, 2017 by rayx

[kton200281]

54 minutes ago, rayx said:

Are the videos and schemas not clear enough? No sucking, no blowing, that hole only allows to equalize the pressure. So that might "pulse", but no permanent blowing or sucking allowed, that points at the problem on the main diagraphm = it´is rupted/cracked.

 

If you block that hole on idling engine, it must not react at all, if it does, diagraphm is KO.

That's great, thank you. there's definitely air coming out of it, and for the size of the hole its quite apparent too. i would describe it as if blowing steadily through a small drinking straw. Am not sure if i can get the diagraphm separately. Are you 100% sure re the fact there should be no blowing air / intake of air? I only ask as a lot of the links above have air coming out of the units. 

 

[Rooster83]

New member weighing in here - I also had rough/lumpy and seeking idle RPM on my 2006 VRS.  When I blocked the PCV valve breather the engine was noticeably worse, juddering etc. 

 

I replaced the PCV valve (15 minute job + about £20 part thanks eBay!) -- cured the problem 100%, also when I block the new breather post-fix it has no effect on RPM at all.

 

It's so cheap & easy to do its probably worth doing anyway.

 

[kton200281]

My idle doesn't change at all, sits at 800rpm. but i feel jolts / shakes randomly through the car and sometimes a feeling that it is misfiring but no check engine light - all of this is at idle only. I understand this could be carbon build up but i had the inlet inspected when an injector was replaced and it was reported as not being too bad so looking at alternatives.

Edited 19 December, 2017 by kton200281

[Rooster83]

When you say "idle doesn't change at all, sits at 800rpm. "  do you mean generally or when covering the breather hole?

 

If the engine running changes at all when covering that then I think the PCV diaphragm inside is shot and needs replacing.

 

(If you cover the PCV hole and it doesn't change then problem must be something else)

[kton200281]

I mean generally - i.e. when i sit in the car the tacho doesn't move despite feeling engine shakes / jolts. They are relatively minor, but you can feel them through the seat. I haven't blocked the PCV hole to see if it affects the idle, but there is a definite escape of air. Will try it and see what happens to the idle. But if the idle is already slightly lumpy, not sure how i will tell if the PCV is bad as presumably blocking it will not make a difference.