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

S3 knocking sound coming from engine - pls help - getting worried.....

Discussion in 'A3/S3/Sportback (8P Chassis)' started by Denty, Nov 9, 2011.

  1. Denty
    Offline

    Denty Member

    Joined:
    Dec 27, 2007
    Messages:
    260
    Likes Received:
    18
    [Nov 9, 2011]
    Hello people, hope ur all well.

    My 08 S3 has developed a knocking sound from the engine bay when you pullaway from a standstill or if your in neutral and rev it.

    About 2 seconds after you rev the engine it knocks once and only once. It does this if your stationary with the car in neutral, clutch up or down. Its only ever one knock, like i said, it happens after a couple of seconds after initial take up or revving. It seems to get a bit louder the higher i rev it but its only ever one knock....

    Any ideas as im getting para the engine is gonn blow up etc...

    Looking forward to your reply guys

    Cheers:thumbsup:
    #1
  2. S3Alex
    Online

    S3Alex Rarely neutral

    Joined:
    Dec 3, 2008
    Messages:
    6,909
    Likes Received:
    1,918
    [Nov 9, 2011]
    Possibly the DMF is knackered,as it's the only thing I can think of that would do something like that....certainly needs someone to look at it.
    #2
  3. Denty
    Offline

    Denty Member

    Joined:
    Dec 27, 2007
    Messages:
    260
    Likes Received:
    18
    [Nov 9, 2011]
    I had the clutch replace at APS and they said my DMF was fine so...... cheers anyway mate
    #3
  4. Denty
    Offline

    Denty Member

    Joined:
    Dec 27, 2007
    Messages:
    260
    Likes Received:
    18
    [Nov 9, 2011]
    ANY OTHER IDEAS??
    #4
  5. S3Alex
    Online

    S3Alex Rarely neutral

    Joined:
    Dec 3, 2008
    Messages:
    6,909
    Likes Received:
    1,918
    [Nov 9, 2011]
    Did they replace the DMF at the same time?

    This seems to be what most recommend,but good luck in getting to the bottom of this.
    #5
  6. Denty
    Offline

    Denty Member

    Joined:
    Dec 27, 2007
    Messages:
    260
    Likes Received:
    18
    [Nov 10, 2011]
    No they said the DMF was fine with little or no movement so they just cleaned the face of it....

    Ive been looking on the forums but this seems like a new one if its not DMF related.

    Me thinks im gonna be buying a mechanics stethascope to try and figure out exactly where its coming from....:doctor:


    any other suggestions welcome
    #6
  7. One Spoke
    Offline

    One Spoke Member

    Joined:
    Feb 5, 2010
    Messages:
    267
    Likes Received:
    0
    [Nov 10, 2011]
    Engine mount?
    #7
  8. leach76
    Offline

    leach76 Member

    Joined:
    Feb 26, 2009
    Messages:
    333
    Likes Received:
    4
    [Nov 15, 2011]
    My thoughts also or dog bone mount etc
    #8
  9. Denty
    Offline

    Denty Member

    Joined:
    Dec 27, 2007
    Messages:
    260
    Likes Received:
    18
    [Nov 17, 2011]
    well i think ive figured out what the 'knocking' was - it seems to be coming from my twintakes wing side airfilter.... had a quick look and it had some leaves and stuff inside, gave it a quick clean and all seems ok now!:thumbsup:

    Its mad how the noise was amplified so much, up thru the car and sounded like it was the engine ..... relieved now tho.
    #9
  10. warren_S5
    Offline

    warren_S5 Moderator Staff Member Moderator VCDS Map User

    Joined:
    Oct 31, 2007
    Messages:
    7,230
    Likes Received:
    2,443
    [Nov 17, 2011]
    Bizarre, but when I fitted my ITG intake it amplified the sounds of the HPFP running so you could hear it ticking at above 6000rpm. Ended up fitting acrylic washers between the main mounting points to the engine block and the metal washers to quieten it down.
    #10
  11. Denty
    Offline

    Denty Member

    Joined:
    Dec 27, 2007
    Messages:
    260
    Likes Received:
    18
    [Nov 17, 2011]
    yea it was a funny one, had me worried for a few days i tell ya! good one making your less noisy warren, nice tip.

    Think im gonna gold tape wrap mine next...then fit a twincooler when funds allow....:yes:
    #11
  12. Denty
    Offline

    Denty Member

    Joined:
    Dec 27, 2007
    Messages:
    260
    Likes Received:
    18
    [Nov 29, 2011]
    ok ok, I thought it was the twintake making the singular knocking noise when pulling away - turns out it wasnt, it was the dump valve/dump valve hose.... when i pinch the hose with some lockable pliers it stops knocking..... the pipe was deforming and causing some sort of vacume thing - got a new uprated forge silicon hose on the way now:cool:
    #12

Share This Page