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

Exhaust flaps (S3) - modify?

Discussion in 'New A3/S3 (8V Chassis)' started by Itguy, Mar 29, 2014.

  1. Itguy
    Offline

    Itguy Well-Known Member

    Joined:
    Oct 25, 2013
    Messages:
    1,130
    Likes Received:
    446
    [Mar 29, 2014]
    Ok people, let's get some collective brain power on this one.


    The exhaust flaps on our S3s must have a way of being tied open all the time surely - either electrically or manually with wire.


    I'm interested in this because my inner pipes are such a PITA to clean, the bit of black soot seems to just weld itself on and I'm having to resort to fine wire wool every wash now.


    I remember on the Aston V8 vantage it was a fuse that could be removed to leave them open all the time and I seem to remember there was something on the old RS3 that someone figured out.


    Anyone got any ideas how they work on our cars? Anyone got their standard exhaust on the bench after having a whole new system fitted?


    Are the flaps usually shut and then powered open or the other way around?


    Cheers
    #1
  2. steeve
    Offline

    steeve Well-Known Member

    Joined:
    Nov 4, 2004
    Messages:
    1,787
    Likes Received:
    644
    [Mar 29, 2014]
    Certainly on the R32 Golf I had you disconnected the pipe to the mechanism on the silencer and plugged it with something most people used a bolt.
    Not sure if the S3 is the same, I'm sure some one on here will know.
    #2
  3. Pulp84
    Offline

    Pulp84 Well-Known Member

    Joined:
    Aug 17, 2013
    Messages:
    1,850
    Likes Received:
    674
    [Mar 29, 2014]
    Think you might need to use a proper metal cleaner rather than worrying about adjusting the exhaust system.

    My A1 185 has the same issue with carbon heavy deposits on the exhaust. Really annoyed me when I got it as my Mk5 GTI never did it. In the end I found this stuff the best Meguiars NXT Generation All Metal Polish - Clean Your Car.

    Over time fine wire wool will take the lustre away from the pipes. Using this stuff seems to build up a bit of a resistance for deposits sticking.
    #3
  4. veeeight
    Online

    veeeight I am a very pretty girl

    Joined:
    Jul 14, 2012
    Messages:
    4,317
    Likes Received:
    2,370
    [Mar 29, 2014]
    That was using a vacuum actuator, same with the 8P S3. Just plug the vacuum pipe, and tie the valve flap rod open.


    Unfortunately the 8V is an electrically actuated (motor) system. You could try unplugging the motor and see if it throws up any Faults in VCDS.


    edit: Actually, don't do that. It may need VCDS to clear the fault code.
    From memory, the flaps open at idle, then shut until around 3000rpm, then open again. In Dynamic mode, they might be open all the time? If you do force them open 100% of the time, you could get unwanted boominess in the cabin.
    Last edited: Mar 29, 2014
    #4
  5. Itguy
    Offline

    Itguy Well-Known Member

    Joined:
    Oct 25, 2013
    Messages:
    1,130
    Likes Received:
    446
    [Mar 29, 2014]
    Yep, that's the metal polish I've been using and it almost works but not really well enough and I certainly haven't been expecting to have to *polish* them every single week - wash yes! Polish no.
    #5
  6. Pulp84
    Offline

    Pulp84 Well-Known Member

    Joined:
    Aug 17, 2013
    Messages:
    1,850
    Likes Received:
    674
    [Mar 29, 2014]
    I'm very surprised by that as it's fantastic stuff! Bit worried now for when mine comes!
    #6
  7. Scott
    Offline

    Scott Well-Known Member

    Joined:
    Mar 10, 2009
    Messages:
    1,281
    Likes Received:
    118
    [Mar 29, 2014]
    I was thinking exactly the same the other day. I have VCDS so if anything needs resetting, that's ok, and I don't mind being a guinea pig. I thought the flaps opened >2500rpm or something like that?
    #7
  8. Itguy
    Offline

    Itguy Well-Known Member

    Joined:
    Oct 25, 2013
    Messages:
    1,130
    Likes Received:
    446
    [Mar 29, 2014]
    Yes I think that's right Scott. Want to have a play?
    #8
    Scott likes this.
  9. RobH_S3
    Offline

    RobH_S3 Active Member

    Joined:
    Sep 16, 2013
    Messages:
    410
    Likes Received:
    186
    [Mar 29, 2014]
    Why don't you just set the exhaust to dynamic mode in the individual setting in the mmi to begin with?

    I can confirm that when unplugged it does show an exhaust flap fault in vcds.
    #9
  10. Itguy
    Offline

    Itguy Well-Known Member

    Joined:
    Oct 25, 2013
    Messages:
    1,130
    Likes Received:
    446
    [Mar 29, 2014]
    I have and always have had it in this setting. It still seems as though the flaps only open at 2.5k revs.

    Now I wonder if there is somewhere in VCDS that you can adjust the flap opening rpm?!
    #10
  11. Scott
    Offline

    Scott Well-Known Member

    Joined:
    Mar 10, 2009
    Messages:
    1,281
    Likes Received:
    118
    [Mar 29, 2014]
    Did it make a sound difference with it unplugged?
    #11
  12. veeeight
    Online

    veeeight I am a very pretty girl

    Joined:
    Jul 14, 2012
    Messages:
    4,317
    Likes Received:
    2,370
    [Mar 29, 2014]
    Logging Measuring Blocks 245, 246 and 247 will tell you at what RPM the flaps are open or shut.

    It's either fully closed, or fully (90%) open. No in between.
    #12
  13. Scott
    Offline

    Scott Well-Known Member

    Joined:
    Mar 10, 2009
    Messages:
    1,281
    Likes Received:
    118
    [Mar 29, 2014]
    Interesting. Thanks. I just unplugged what I assume are the flaps lol but not sure whether it's made a difference or not. I'll get VCDS and check what's going on
    #13
  14. Scott
    Offline

    Scott Well-Known Member

    Joined:
    Mar 10, 2009
    Messages:
    1,281
    Likes Received:
    118
    [Mar 29, 2014]
    Ok we have fault codes

    2 Faults Found:
    21388 - Valve for Exhaust Flap 1 (N321)
    P3019 00 [047] - Open Circuit
    Confirmed - Tested Since Memory Clear
    Freeze Frame:
    Fault Status: 00000001
    Fault Priority: 2
    Fault Frequency: 1
    Mileage: 3879 km
    Date: 2014.03.29
    Time: 20:28:48

    21399 - Valve for Exhaust Flap 2 (N322)
    P3023 00 [039] - Open Circuit
    Not Confirmed - Tested Since Memory Clear
    Freeze Frame:
    Fault Status: 00000001
    Fault Priority: 2
    Fault Frequency: 1
    Mileage: 3879 km
    Date: 2014.03.29
    Time: 20:33:30

    No warning lights

    Sounds quite loud on idle in front of the garage. I will do some testing tomorrow and see what someone else thinks. I will also check measuring blocks but the battery on my laptop was 2% so it died before I was able to
    #14
  15. Scott
    Offline

    Scott Well-Known Member

    Joined:
    Mar 10, 2009
    Messages:
    1,281
    Likes Received:
    118
    [Mar 29, 2014]
    Ok I'm not convinced I can tell a difference. If anything, it might be quieter at higher RPM's. I guess the flaps would need to be disconnected when they are open e.g. >2500rpm otherwise they would simply stay closed?
    #15
  16. veeeight
    Online

    veeeight I am a very pretty girl

    Joined:
    Jul 14, 2012
    Messages:
    4,317
    Likes Received:
    2,370
    [Mar 29, 2014]
    I think they are open by default when the car is switched off.
    #16
  17. Scott
    Offline

    Scott Well-Known Member

    Joined:
    Mar 10, 2009
    Messages:
    1,281
    Likes Received:
    118
    [Mar 29, 2014]
    I think you're right actually as I remember VCDS saying 'Open' when it was idling

    Anyway I'll give it a blast tomorrow and see what I think

    Need to tape up the connectors so they don't get dirty too
    #17
  18. Itguy
    Offline

    Itguy Well-Known Member

    Joined:
    Oct 25, 2013
    Messages:
    1,130
    Likes Received:
    446
    [Mar 29, 2014]
    Good lad, waiting with bated breath!

    Would probably be easy to see if the flap was open when car off too by inserting something flexible up the pipe maybe?
    #18
  19. Scott
    Offline

    Scott Well-Known Member

    Joined:
    Mar 10, 2009
    Messages:
    1,281
    Likes Received:
    118
    [Mar 30, 2014]
    I'll let you insert something flexible up the exhaust haha :p
    #19
    S3piper and veeeight like this.
  20. Itguy
    Offline

    Itguy Well-Known Member

    Joined:
    Oct 25, 2013
    Messages:
    1,130
    Likes Received:
    446
    [Mar 30, 2014]
    :yum:
    #20
    Scott likes this.
  21. veeeight
    Online

    veeeight I am a very pretty girl

    Joined:
    Jul 14, 2012
    Messages:
    4,317
    Likes Received:
    2,370
    [Mar 30, 2014]
    Are you offering up your exhaust Scott ;)

    Form an orderly queue :p
    #21
    Scott likes this.
  22. PilotAudi
    Offline

    PilotAudi New Member

    Joined:
    Oct 4, 2009
    Messages:
    2,352
    Likes Received:
    478
    [Mar 30, 2014]
    I've found a quick raid in the kitchen to get some of this stuff works a treat.

    Cif | Stainless Steel

    Use with very fine wire wool if/when stubborn blackness needs removing, then just wipe clean... Mrs isn't that impressed though ;-)

    On the noise front.. it's a bit annoying that at 75-85mph in 6th the noise is at it's most annoying. Just the sort of motorway/autoroute cruising speed I like!
    #22
  23. Itguy
    Offline

    Itguy Well-Known Member

    Joined:
    Oct 25, 2013
    Messages:
    1,130
    Likes Received:
    446
    [Mar 30, 2014]
    Well I've just been outside to see what I could test (don't have VCDS) and it seems like the valves are open when the car is off, and with the ignition on and with the car running at idle. I used a long flexible grabber that I've got in the garage and it certainly went in far enough to go past where the valve is located. Obviously couldn't test it at 3 or 4k rpm to see if the valve was open, shut etc. So maybe to only closes between off-idle and 2.5k??
    #23
    Scott likes this.
  24. Scott
    Offline

    Scott Well-Known Member

    Joined:
    Mar 10, 2009
    Messages:
    1,281
    Likes Received:
    118
    [Mar 30, 2014]
    Lol.

    Ok all looks good to me. Doesn't sound too loud/boomy. I haven't tested on the motorway but I've tested on some quiet A roads. 30mph in 4th sounds louder, but not too loud, and certainly not noticeable with the windows closed/music up :laugh:

    Still no warning lights, just the faults logged on VCDS.

    Easy enough to tape up the plugs/connectors with some electrical tape to protect them.

    I'd recommend it.
    #24
  25. Itguy
    Offline

    Itguy Well-Known Member

    Joined:
    Oct 25, 2013
    Messages:
    1,130
    Likes Received:
    446
    [Mar 30, 2014]
    I wonder if there is anything that could be monitored in VCDS while driving to see what the normal flap behaviour is in the different individual modes (comfort, auto and dynamic)??

    Interesting that you can hear a difference. Is it a noticeable change over 'dynamic' when just pottering around then (windows shut)?
    #25
  26. veeeight
    Online

    veeeight I am a very pretty girl

    Joined:
    Jul 14, 2012
    Messages:
    4,317
    Likes Received:
    2,370
    [Mar 30, 2014]
    Yes.
    Logging Measuring Blocks 245, 246 and 247 (plus RPM) in all the different Drive Modes will tell you at what RPM the flaps are open or shut.
    #26
  27. Itguy
    Offline

    Itguy Well-Known Member

    Joined:
    Oct 25, 2013
    Messages:
    1,130
    Likes Received:
    446
    [Mar 31, 2014]
    Scott, another one for you mate as you have VCDS. I wonder if it is worth also recording throttle angle as the behaviour might be linked to that too??
    #27
  28. Itguy
    Offline

    Itguy Well-Known Member

    Joined:
    Oct 25, 2013
    Messages:
    1,130
    Likes Received:
    446
    [Mar 31, 2014]
    #28
  29. Silky-S3
    Offline

    Silky-S3 Is loving his new 8V S3!

    Joined:
    Jan 30, 2009
    Messages:
    1,399
    Likes Received:
    317
    [Mar 31, 2014]
    I'd like to do this. Scott, so it's just case of getting under the car and unplugging the connectors? The valves stay open all the time then?

    I have VCDS so happy to do some logging if it helps the cause.
    #29
  30. Itguy
    Offline

    Itguy Well-Known Member

    Joined:
    Oct 25, 2013
    Messages:
    1,130
    Likes Received:
    446
    [Mar 31, 2014]
    That's what I understand. The flaps are electric obviously and are in a normally open state so I figure that as long as they are unplugged while open, they will stay open. A short burst of logging would be interesting just to know when the flaps usually are open / shut so we can tell where abouts we should hear a difference after unplugging / always open
    #30
  31. Scott
    Offline

    Scott Well-Known Member

    Joined:
    Mar 10, 2009
    Messages:
    1,281
    Likes Received:
    118
    [Apr 1, 2014]
    It's very slightly noticeably louder with the windows closed but certainly nothing to write home about. It's a louder at slow speed/low rev driving and on acceleration from low rpm. It's a good improvement IMO. And yeh, just unplug the connectors on both sides and tape them up with some electrical tape to keep 'em clean :)
    #31
  32. Scott
    Offline

    Scott Well-Known Member

    Joined:
    Mar 10, 2009
    Messages:
    1,281
    Likes Received:
    118
    [Apr 1, 2014]
    I'll do some logging, if no one else has, next week as I'm off to Spain tomorrow (last minute thing)
    #32
  33. Itguy
    Offline

    Itguy Well-Known Member

    Joined:
    Oct 25, 2013
    Messages:
    1,130
    Likes Received:
    446
    [Apr 1, 2014]
    #33
  34. Itguy
    Offline

    Itguy Well-Known Member

    Joined:
    Oct 25, 2013
    Messages:
    1,130
    Likes Received:
    446
    [Apr 1, 2014]
    Ok, have unplugged mine tonight without having to jack up the car etc, the plugs are easily accessible. Taped them up and cable tied the out of the way.

    Have a very quick run up and down the road and didn't really see any difference but it was such a short run, tomorrow morning will be the tell-tail run.

    As another thought, does the dash noise generator always work in all driving modes or does that change too? I like to drive my commute in efficiency mode but want it loud!
    #34
  35. rigger
    Offline

    rigger Member

    Joined:
    Sep 30, 2013
    Messages:
    56
    Likes Received:
    15
    [Apr 1, 2014]
    The dash noise generator will open only on dynamic or set manually via individual.
    Cant set efficiency and get sound :busted_cop:
    #35
  36. Scott
    Offline

    Scott Well-Known Member

    Joined:
    Mar 10, 2009
    Messages:
    1,281
    Likes Received:
    118
    [Apr 2, 2014]
    The only time you really notice (IMO) is when the engine is warm and slow speed stuff, pulling off, accelerating from low revs in high gears, it just gives a bit more sound. It's not noticeable at all really, but if you listen with the window down, it definitely makes a difference outside
    #36
    The Challinor likes this.
  37. Aran383
    Offline

    Aran383 Active Member

    Joined:
    Apr 18, 2013
    Messages:
    106
    Likes Received:
    89
    [Apr 10, 2014]
    I just did this mod today, definitely a slight difference in noise - more boom, think the car should have come stock like this IMHO. Have the rest of you left it unplugged or have you returned it back to stock?
    #37
  38. Itguy
    Offline

    Itguy Well-Known Member

    Joined:
    Oct 25, 2013
    Messages:
    1,130
    Likes Received:
    446
    [Apr 10, 2014]
    Mines been unplugged for a week now. Makes all 4 exhausts equally dirty now and actually much easier to clean as the soot concentration is now over 4 pipes rather than 2.

    I'm loving the sound and as I typically stick mine in Eco mode for my commute
    #38
  39. Scott
    Offline

    Scott Well-Known Member

    Joined:
    Mar 10, 2009
    Messages:
    1,281
    Likes Received:
    118
    [Apr 11, 2014]
    Mine's still unplugged
    I want more sound now ;)
    #39
  40. Aran383
    Offline

    Aran383 Active Member

    Joined:
    Apr 18, 2013
    Messages:
    106
    Likes Received:
    89
    [Apr 11, 2014]
    That's good! Always find it a pain having to clean the inner pipes if I don't wash it for more than a week
    #40
    The Challinor likes this.

Share This Page