Exhaust burble/raspberry

Discussion in '3 Series' started by Cascades, Jan 9, 2019.

  1. Cascades
    Offline

    Cascades

    Joined:
    Jan 9, 2019
    Messages:
    2
    Likes Received:
    0
    Ratings:
    +0 / 0 / -0
    Hi Guys,
    I have a 2005 E90 330i with 69,000 miles. Over the last few months the exhaust has developed a burbling/blowing a raspberry noise at around 1500 rpm. It fades away after 2000 rpm. It is only evident under load i.e. I cannot reproduce it when the car is stationary. I cannot believe it is anything serious but it is annoying and detracts from what otherwise is a superb car. Does anyone have any ideas ? Thanks in advance.
     
  2. bishbosh
    Online

    bishbosh WARLORD Site Supporter

    Joined:
    Aug 15, 2015
    Messages:
    1,204
    Likes Received:
    411
    Ratings:
    +635 / 3 / -0
    Hole in the exhaust?
     
  3. snrbrtsn
    Offline

    snrbrtsn WARLORD Site Supporter

    Joined:
    Jul 30, 2015
    Messages:
    1,734
    Likes Received:
    641
    Location:
    Aberdeen
    Ratings:
    +1,026 / 0 / -1
    It may be the tone difference when the second pipe opens
    Though it could also be a cracked flexi joint
    Worth checking the mounting at the gearbox as prone to breaking there
     
  4. Cascades
    Offline

    Cascades

    Joined:
    Jan 9, 2019
    Messages:
    2
    Likes Received:
    0
    Ratings:
    +0 / 0 / -0
    Thanks for this. When sitting in the drivers seat the noise appears to be coming from the direction of the gearbox so it could be your last suggestion.
    Reading your first suggestion, my eyes glazed over at the phrase "when the second pipe opens". Could you please explain to an ignoramus. Thanks.
     
  5. snrbrtsn
    Offline

    snrbrtsn WARLORD Site Supporter

    Joined:
    Jul 30, 2015
    Messages:
    1,734
    Likes Received:
    641
    Location:
    Aberdeen
    Ratings:
    +1,026 / 0 / -1
    Can’t find a picture
    The exhaust should have twin tail pipes on the left hand side, one pipe is straight through the other should have a vacuum controlled flap.
    This allows for silence when idling through single pipe and a slight throaty burble when the rpm is increased through both pipes
    The bigger the engine the more noticeable.
     

Share This Page