Notices
 
 

  

User Tag List

Thread: A4 B5 AEB engine PCV valve position

Results 1 to 3 of 3
  1. A4 B5 AEB engine PCV valve position 
    #1
    Join Date
    Mar 2016
    Location
    Minervois, France
    Posts
    591
    Post Thanks / Like
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    53 Post(s)
    I replaced my PCV valve some time ago as part of my attempts to reduce my oil consumption. The new valve didn't make any noticeable difference and the one I removed seems to operate correctly.

    The old valve is still sitting on my desk, and I just, rather belatedly, noticed that the hose connection stubs on it are marked "K" and "F". The letters are just about visible in the image below.

    As one connection goes to the turbocharger inlet pipe I guess that "K" stands for "Kompressor", and "F" for perhaps "Falle" = trap, maybe the oil separator/catch can/trap.

    The valve, has a diaphragm at the top, with atmospheric pressure above it, and turbo suction below, so that increasing suction will pull the diaphragm towards the "F" pipe, closing off the top of this, and restricting the flow of gas to that through a hole of about 3 mm diameter in the side.

    Looking at the cross section of the valve in my sketch, it seems obvious that "K" should go to the turbo inlet pipe, and "F" to the crankcase breather assembly, but the valve is installed the other way around, and also appears to be that way in the drawings of the turbo piping in the Bentley manual.

    The pics below show the valve, where it is installed, and my sketch of its cross section. Can anyone confirm the correct mounting position, please?

    PCV valve.JPGPCV valve location.jpgPCV valve section.jpg
    Did this forum help you? Help make sure it's here next time! Follow the instructions at the top of the page to make a suitable donation using PayPal .
    1996 A4 B5 (S2) Avant 1.8T (petrol) 150 bhp code AEB automatic with 79,125 kms = 49,450 miles on 30/07/23
    VW T25 Camper, Alfa 33 1.4 ie, 2 Alfa 33's for parts.
     
    0 0 0
     

  2. Re: A4 B5 AEB engine PCV valve position 
    #2
    Join Date
    Mar 2016
    Location
    Minervois, France
    Posts
    591
    Post Thanks / Like
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    53 Post(s)
    I finally found an explanation of the valve's operation on a German website. The "K" stands for Kurbelgehäuse - crankcase, so the valve is the right way round. Don't know what he "F" stands for.

    When the engine begins to run, the pressure at "K" is below atmospheric, so the diaphragm and its sealing disc move down, closing off the connection to the turbo suction except for via the 3 mm hole.

    As crankcase pressure at "K" increases, the diaphragm moves up, allowing the gases entering via "K" to go out through "F" in a controlled way, keeping crankcase pressure slightly below atmospheric, this difference in pressure being determined by the strength of the spring.

    If the diaphragm fails, a very small amount of air will get into the turbo inlet though the small hole above the diaphragm. This would be compensated for by the engine management system, and would probably show up on a scan as an unusual mixture correction.

    The integrity of the diaphragm can be easily checked by blocking the end of one connection with a finger, and blowing into the other. A puff of air from the space above the diaphragm should be heard coming out of the little hole opposite "K", but no more than that. This could be confirmed by immersing the hole in water and having someone watch the bubbles as you blow, but this might result in water being sucked into the space above the diaphragm.

    Link to German explanation https://www.motor-talk.de/bilder/n57...209260770.html
    Did this forum help you? Help make sure it's here next time! Follow the instructions at the top of the page to make a suitable donation using PayPal .
    1996 A4 B5 (S2) Avant 1.8T (petrol) 150 bhp code AEB automatic with 79,125 kms = 49,450 miles on 30/07/23
    VW T25 Camper, Alfa 33 1.4 ie, 2 Alfa 33's for parts.
     
    0 0 0
     

  3. Re: A4 B5 AEB engine PCV valve position 
    #3
    Join Date
    Jan 2007
    Location
    Nottingham, England
    Posts
    42,103
    Post Thanks / Like
    Blog Entries
    4
    Mentioned
    108 Post(s)
    Tagged
    1 Thread(s)
    Quoted
    1816 Post(s)
    Kurbelgehäuse, rotary house or Kurbelwelle Gehause, crankshaft housing.
    Anthropogenic climate change, the biggest con inflicted on mankind since religion...

    Slava Ukraini
    !


     
    0 0 0
     

Similar Threads

  1. Throttle position sensor BLB engine
    By Dozy in forum Audi A6 - C6 Forum - 2005 - 2010
    Replies: 5
    Last Post: 16-03-2013, 08:54 AM
  2. Question engine sensor position
    By davison in forum Touran - Sharan - Caravelle
    Replies: 5
    Last Post: 14-01-2012, 01:13 PM
  3. egr valve position and removal passat 2.5 v6 tdi
    By jemp in forum Passat - B5 Forum - 1997 -2005
    Replies: 3
    Last Post: 08-09-2010, 02:00 PM
  4. throttle position sensor Dump Valve
    By ns_sullivan in forum Golf MK4 - 1999 - 2004
    Replies: 0
    Last Post: 25-06-2008, 10:56 AM
  5. engine number position
    By Turkster in forum Passat - Archive Topics
    Replies: 0
    Last Post: 17-09-2007, 01:00 AM
Bookmarks
Bookmarks
Posting Permissions
  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


 



  


Disclaimer: VW Audi Forum is an "independant enthusiast website", administered in line with guidelines supplied by VAG in the UK, and is in no way related to any of the Worldwide Volkswagen,Audi,Seat,Skoda,Bentley,Bugatti,Porsche or Lamborghini group of Companies. For official up to date information on any of there vehicles, please visit the official websites. Any comments made throughout this website, are the views of the respective poster, and in no way represent the views of the VW Audi Forum Administration, or the worldwide Volkswagen & Audi Group of companies.


VW Audi Forum do not vet and are not responsible for any information which is posted in this forum. All content is viewed and used by you at your own risk and we do not warrant the accuracy or reliability of any of the information.


Copyright: Certain "words", "phrases" and "Images" used on this website by the Administration are "Copyright" of Volkswagen GB, Volkswagen AG (Germany), Audi GB, Audi AG (Germany), Volkswagen Motorsport GB, Volkswagen Motorsport AG (Germany), Audi Motorsport AG (Germany), Volkswagen Racing GB, Bentley, Bugatti, Porsche and Lamborghini. No image can be replicated by anyone WITHOUT the relevant Companies written permission.


All trademarks and copyrights remain property of their respective owners.

No part of the VW Audi Forum website or forum may be reproduced without written permission from the site administration


PLEASE NOTE - PERSONAL ABUSE, ABUSE AGAINST THIS OR ANY OTHER WEBSITE OR ANY COMPANY WILL NOT BE TOLERATED. OFFENDERS WILL BE MODERATED OR EVEN BANNED.


This website and forum are best viewed at a minimum resolution of 1024 by 768.



  



- VW AUDI Forum - The #1 Volkswagen (VW) Group Forum - Volkswagen (VW) - Audi - Seat - Skoda - Bentley - Bugatti - Lamborghini - Porsche - Scania - MAN - Ducatti - VW Audi Forum -


- www.vwaudiforum.co.uk - www.vwaudiforum.co.uk -