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OK - another silly question.

Discussion in 'Z3 Roadster & Coupé' started by t-tony, Apr 16, 2014.

  1. t-tony

    t-tony Zorg Expert (I)
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    On my 2.0 Auto the rear silencer has 2 outlets, one of which has/had a vacuum operated "flap" inside it. As far as I'm aware this flap has not operated since I've had the car. Silly questions are: What does it do? and as mine is stuck wide open does it affect the way the engine runs? Fitted a new inlet camshaft position sensor today at work as it was quiet and she has not run so well since I've had her.:)
     
  2. Brian4

    Brian4 Zorg Guru (IV)
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    I have read somewhere that the auto's don't have the flap in the exhaust. The operating unit is in the left rear well under the tilt sensor. Our 3.0 auto has the switch but I can see nowhere to fix the vacuum pipe to the exhaust.
     
  3. GazHyde

    GazHyde The Gaz Monkey
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    It's a butterfly valve which at low speeds keeps the engine noise down. When you floor it opens up and allows more noise.
     
  4. t-tony

    t-tony Zorg Expert (I)
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    Thanks Gary, that's roughly what I thought. I can remember soon after getting the car I floored it onto the roundabout at the road out of Lincoln one night but then had to back off and there was an almighty crack at the back of the car and I assume that was when it ceased to work. It does have a vacuum pipe connected but with the engine running I cant detect any vacuum on the pipe with a gauge connected. The flap itself is jammed open so because I like noise I think I'll leave well alone.
     
  5. hard top

    hard top Zorg Expert (I)
    Dutch Zeds The M44 Massive

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    What, one of these.....

    [​IMG]
     
    • Funny Funny x 1
  6. t-tony

    t-tony Zorg Expert (I)
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    OOh nooooo.:)
     

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