1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

N249 Bypass on a BAM

Discussion in 'A3/S3 Forum (8L Chassis)' started by S3featesV9, Jun 27, 2011.

  1. S3featesV9
    Offline

    S3featesV9 Active Member

    Joined:
    Dec 8, 2010
    Messages:
    1,033
    Likes Received:
    12
    [Jun 27, 2011]
    is there a thread showing how to do this on a BAM. ive seen one or two but arent for a BAM.

    all i need is a 1meter lenght of 4mm ID hose? and a T-piece?

    Any help, thanks!
    #1
  2. Ads

    Ads

    [Sep 22, 2014]

  3. S3featesV9
    Offline

    S3featesV9 Active Member

    Joined:
    Dec 8, 2010
    Messages:
    1,033
    Likes Received:
    12
    [Jun 27, 2011]
    #2
  4. S3Lol
    Offline

    S3Lol Member

    Joined:
    Jul 19, 2009
    Messages:
    425
    Likes Received:
    7
    [Jun 27, 2011]
    Ill take a pic of mine later. really easy to do. If you follow the tube from the 249 down, it connects underneath the intake manifold. All you are doing is taking a 4mm vac hose from there to the top of the DV. No t-piece required
    #3
  5. Alex C
    Online

    Alex C Well-Known Member

    Joined:
    Jan 26, 2010
    Messages:
    2,671
    Likes Received:
    160
    [Jun 27, 2011]
    no SAI, so no need for a T piece.

    Just the 4mm ID hose from the inlet manifold to the top of the DV
    #4
  6. S3featesV9
    Offline

    S3featesV9 Active Member

    Joined:
    Dec 8, 2010
    Messages:
    1,033
    Likes Received:
    12
    [Jun 27, 2011]
    whats a SAI? not that it matters if i dont have one. just curious.

    thanks S1, that will be a great help.
    #5
  7. Alex C
    Online

    Alex C Well-Known Member

    Joined:
    Jan 26, 2010
    Messages:
    2,671
    Likes Received:
    160
    [Jun 27, 2011]
    SAI -> Secondary Air Injection

    it helps the CAT warm up quicker and improves emmisions on cold starts i think
    #6
  8. S3featesV9
    Offline

    S3featesV9 Active Member

    Joined:
    Dec 8, 2010
    Messages:
    1,033
    Likes Received:
    12
    [Jun 27, 2011]
    #7
  9. S3Lol
    Offline

    S3Lol Member

    Joined:
    Jul 19, 2009
    Messages:
    425
    Likes Received:
    7
    [Jun 27, 2011]
    just uploading the video for you now
    #8
  10. Alex C
    Online

    Alex C Well-Known Member

    Joined:
    Jan 26, 2010
    Messages:
    2,671
    Likes Received:
    160
    [Jun 27, 2011]
    the black box behind the N249 is the vacuum reservoir, it will be removed when doing the bypass
    #9
  11. S3featesV9
    Offline

    S3featesV9 Active Member

    Joined:
    Dec 8, 2010
    Messages:
    1,033
    Likes Received:
    12
    [Jun 27, 2011]
    i see, so after ive done this...all that messy hose setup will be gone? along with the n249 and vacuum reservior?
    #10
  12. Alex C
    Online

    Alex C Well-Known Member

    Joined:
    Jan 26, 2010
    Messages:
    2,671
    Likes Received:
    160
    [Jun 27, 2011]
    yep, you'll just have one hose
    #11
  13. aragorn
    Offline

    aragorn "Stick a V8 in it!" Staff Member Moderator VCDS Map User

    Joined:
    Jan 30, 2008
    Messages:
    15,575
    Likes Received:
    314
    [Jun 27, 2011]
    you'll need to keep the N249 plugged in though, or replace it with a suitable resistor.
    #12
  14. S3featesV9
    Offline

    S3featesV9 Active Member

    Joined:
    Dec 8, 2010
    Messages:
    1,033
    Likes Received:
    12
    [Jun 27, 2011]
    i can keep it plugged in, and just tidy it away somewhere right?
    #13
  15. S3Lol
    Offline

    S3Lol Member

    Joined:
    Jul 19, 2009
    Messages:
    425
    Likes Received:
    7
    [Jun 27, 2011]
    Last edited by a moderator: Aug 15, 2014
    #14
    millermk1, dancarpy, AUSS3 and 2 others like this.
  16. Alex C
    Online

    Alex C Well-Known Member

    Joined:
    Jan 26, 2010
    Messages:
    2,671
    Likes Received:
    160
    [Jun 27, 2011]
    you should keep it plugged in and stow it away somewhere out of the way
    #15
  17. S3Lol
    Offline

    S3Lol Member

    Joined:
    Jul 19, 2009
    Messages:
    425
    Likes Received:
    7
    [Jun 27, 2011]
    please ignore the droning voice today. Not feeling the best. Probably something to do with saturday night and having 2 hours sleep in the car.

    Incase anyone was wondering, I usually have the pipe neatly routed, but thought it was best to show it loose for this demonstration
    Last edited: Jun 27, 2011
    #16
  18. S3featesV9
    Offline

    S3featesV9 Active Member

    Joined:
    Dec 8, 2010
    Messages:
    1,033
    Likes Received:
    12
    [Jun 27, 2011]
    thanks for the vid, perfect bit of info. should get this done at the weekend. or whenever the hose arrives.

    i take it i need the manifold off so i can get to this underside nipple. have had a quick look and cant see it.

    is it advisable to use some spring clips to secure hose on?

    Thanks again
    #17
  19. S3Lol
    Offline

    S3Lol Member

    Joined:
    Jul 19, 2009
    Messages:
    425
    Likes Received:
    7
    [Jun 27, 2011]
    you dont need to take the manifold off. Just take the old pipe off, and slide new pipe on. The old pipe has a clip if I remember rightly, which was a bit of a pain, but flat headed screwdriver prevailed.

    I havent got mine clipped and it is fine. I believe others on here have also not bothered with clips.
    #18
  20. S3featesV9
    Offline

    S3featesV9 Active Member

    Joined:
    Dec 8, 2010
    Messages:
    1,033
    Likes Received:
    12
    [Jun 27, 2011]
    Ok cheers.

    Thanks for all your help bud. :thumbsup:
    #19
  21. S3Lol
    Offline

    S3Lol Member

    Joined:
    Jul 19, 2009
    Messages:
    425
    Likes Received:
    7
    [Jun 27, 2011]
    no problem. That said, you should take that black plate off at the front of the manifold so its easier to get to :) two hex bolts, easy.

    JUST BE CAREFUL WITH THE DIPSTICK TUBE! Gets very brittle over time and can break. If it does, about a fiver from VAG outlet.
    #20
  22. The Doctor
    Offline

    The Doctor Well-Known Member

    Joined:
    Jul 25, 2009
    Messages:
    1,285
    Likes Received:
    112
    [Jun 27, 2011]
    Great thread, I had the same question so I shall be doing some N249 bypassing one evening soon... :icon_thumright:
    #21
  23. S3featesV9
    Offline

    S3featesV9 Active Member

    Joined:
    Dec 8, 2010
    Messages:
    1,033
    Likes Received:
    12
    [Jun 27, 2011]
    haha yeah, think mine needs replacing anyway so shall do it whilst the bonnets up :)
    #22
  24. AUSS3
    Offline

    AUSS3 2002 S3 BAM

    Joined:
    Jun 18, 2011
    Messages:
    7
    Likes Received:
    0
    [Aug 11, 2011]
    Cheers guys, just ordered my silicone and will get this done sharpish.
    #23
  25. VAG-Slag
    Offline

    VAG-Slag Active Member

    Joined:
    Jul 11, 2011
    Messages:
    572
    Likes Received:
    84
    [Aug 13, 2011]
    nice and simple little vid man, i assume this'll be pretty much exactly the same for AMK as well?
    #24
  26. Slammedorion
    Offline

    Slammedorion Member

    Joined:
    Jul 5, 2006
    Messages:
    96
    Likes Received:
    13
    [Aug 13, 2011]
    Sorry, newbie and all. . . What are the benifits of this mod???
    #25
  27. StaceyS3
    Offline

    StaceyS3 Well-Known Member

    Joined:
    Dec 17, 2010
    Messages:
    2,131
    Likes Received:
    198
    [Aug 13, 2011]
    It lessens the possibility of boost leaks on the system as well as the chances of the dv not opening due to faulty valve etc

    And one of the other reasons is removes unecessary pipe work so tidy's up the bay and the valve will just function mechanically 
    #26
  28. S3Lol
    Offline

    S3Lol Member

    Joined:
    Jul 19, 2009
    Messages:
    425
    Likes Received:
    7
    [Aug 13, 2011]
    check the stickies for guides to other engine codes, but if you dont have the SAI (think thats what its called) then it will be the same.
    #27
  29. S3Lol
    Offline

    S3Lol Member

    Joined:
    Jul 19, 2009
    Messages:
    425
    Likes Received:
    7
    [Aug 13, 2011]
    infact, can a mod take part of this thread and mix it into the guide for the other n249 bypass in the stickies?
    #28
  30. devan
    Offline

    devan Member

    Joined:
    Jun 30, 2010
    Messages:
    119
    Likes Received:
    2
    [Jan 6, 2012]
    Aaaahhh just done the N249 bypass on my BAM engine and when it dumps boost it seems to flutter and make the car jerk :(

    Took me ages getting the silicone pipe nice and neat from the manifold to the DV, and then had to waste more time putting it all back to standard when I realised it hadnt worked as id hoped lol.

    Anybody have an explanation as to why it would be doing this?
    #29
  31. S3 JOHN
    Offline

    S3 JOHN Member

    Joined:
    Dec 13, 2011
    Messages:
    310
    Likes Received:
    3
    [Jan 6, 2012]
    Think the silicone hose you fitted must of had a block in it as it stopped you DV from working.
    #30
  32. S3 JOHN
    Offline

    S3 JOHN Member

    Joined:
    Dec 13, 2011
    Messages:
    310
    Likes Received:
    3
    [Jan 6, 2012]
    Or it was leaking so there wasnt anoth vacum to open the DV
    #31
  33. <tuffty/>
    Offline

    <tuffty/> Badger 5 Edition Staff Member Moderator

    Joined:
    Sep 14, 2008
    Messages:
    15,926
    Likes Received:
    1,338
    [Jan 6, 2012]
    Sounds like the DV is not seeing vacuum... the N249 bypass is stupidly simple on AMK/BAM engine codes... yu litrally run a 4mm ID silicon vacuum pipe from the outlet underneath the inlet manifold (one of the 2 outlets over the alternator) and connect it to the top of the DV... simples..

    No check valves etc at all to worry about...

    Now... there will always be a little flutter on part throttle when loading up (say going up hill) then letting off.. this is normal... if you get flutter just by revving the engine then you have a problem

    <tuffty/>
    #32
  34. devan
    Offline

    devan Member

    Joined:
    Jun 30, 2010
    Messages:
    119
    Likes Received:
    2
    [Jan 8, 2012]
    Yeah theres no doubting that I did it wrong because it is literally so simple on a BAM that I think its impossible to get wrong lol.

    And I gave it a little try out by revving the engine before I set off for a test drive and it sounded ok, but then when I took it out it sounded very wrong when dumping. Just wondering if I tightened up one of the cable ties too tightly when routing the pipe :-/

    Might have to attempt this again when I have a few spare minutes again.
    #33
  35. driftymcgee
    Offline

    driftymcgee Member

    Joined:
    Apr 19, 2010
    Messages:
    44
    Likes Received:
    4
    [Jan 11, 2012]
    where did everyone that's done the delete decide to hide the oddly large valve?
    #34
  36. <tuffty/>
    Offline

    <tuffty/> Badger 5 Edition Staff Member Moderator

    Joined:
    Sep 14, 2008
    Messages:
    15,926
    Likes Received:
    1,338
    [Jan 11, 2012]
    #35
  37. argyle89
    Offline

    argyle89 Member

    Joined:
    Dec 22, 2011
    Messages:
    111
    Likes Received:
    0
    [Jan 11, 2012]
    is this the same for an agu engine? as i cant seem to find my n249?! :s

    Edit: just read that the agu doesnt have a n249 so maybe thats why i cant find it!!??
    Last edited: Jan 11, 2012
    #36
  38. Westy
    Offline

    Westy Double Dark Side! Diesel & 8P

    Joined:
    Dec 2, 2008
    Messages:
    17,297
    Likes Received:
    972
    [Jan 11, 2012]
    #37
  39. <tuffty/>
    Offline

    <tuffty/> Badger 5 Edition Staff Member Moderator

    Joined:
    Sep 14, 2008
    Messages:
    15,926
    Likes Received:
    1,338
    [Jan 11, 2012]
    Maybe you need to spend some time reading it again lol...

    Erm... 'some wire' Bill had on the shelf but 5-10amps rated should do it..

    <tuffty/>
    #38
  40. Westy
    Offline

    Westy Double Dark Side! Diesel & 8P

    Joined:
    Dec 2, 2008
    Messages:
    17,297
    Likes Received:
    972
    [Jan 11, 2012]
    I haven't got that much time :faint:

    I've got a load of wire offcuts at home. Probably be able to use some of the stuff I cut off the AEM controller ;)
    #39
  41. Westy
    Offline

    Westy Double Dark Side! Diesel & 8P

    Joined:
    Dec 2, 2008
    Messages:
    17,297
    Likes Received:
    972
    [Jan 11, 2012]
    Oh and Tuffts, how does your engine cover stay on if you've removed the holder?
    #40

Share This Page