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Idle boost reading

Discussion in 'A3/S3 Forum (8L Chassis)' started by sekenzo, Oct 4, 2011.

  1. sekenzo

    sekenzo Member

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    Can someone confirm what is the normal idle vac reading? I am currently at -0.8 bar... Does this sound like I have a leak?
     
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  3. 16Klappe

    16Klappe I <3 Panda's!
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    Just checked, mine sits at -22PSI.
     
  4. s3gazz

    s3gazz Well-Known Member

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    Mine is -20
     
  5. sekenzo

    sekenzo Member

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    -0.8bar = -11.6 psi.. Sounds like something is wrong...
     
  6. DJ_Troopa

    DJ_Troopa K1 Driver

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    I'm on -13.4. I've also been told i have a boost leak but then i've been told everything is fine? Confused.com
     
  7. 16Klappe

    16Klappe I <3 Panda's!
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    To be fair because it is making negative pressure it will be difficult to tell if and where the boost leak is, you will need to have it vacuum and pressure tested.
     
  8. DaveA3

    DaveA3 Audi A-Trizzle!

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    -20 until i drive it a bit then it goes to -25 when i stop
     
  9. Andy123

    Andy123 Member

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    You want around 19/20 inHg of vacuum, anything much lower would suggest a leak. Not measured in psi by the way, -20psi isn't possible.
     
  10. Westy

    Westy Double Dark Side! Diesel & 8P

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    A lot of guages show hg in vacuum not PSI. mine is around -14hg
     
  11. S3 Paul

    S3 Paul Well-Known Member
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    I was beginning to think i had a problem... Mine has never seen -20 psi !
    I was told mine was "giving a good reading indicating no leaks or problems "
    I will check what it actualy reads later when i head out.
     
  12. Westy

    Westy Double Dark Side! Diesel & 8P

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    I'm sure this subject has come up before and around -13-14hg was about right :think:
     
  13. S3 Paul

    S3 Paul Well-Known Member
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    I was thinking high 'teens
    Different when still on cold start too?
     
  14. Westy

    Westy Double Dark Side! Diesel & 8P

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    This is mine on cold start then it drops a bit when warm:

    [​IMG]
     
  15. s3gazz

    s3gazz Well-Known Member

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    When mine starts (cold) it's 12 psi ish then when warmed it goes to 20 psi
     
  16. Sandip

    Sandip Well-Known Member

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    Mine is -20 in.Hg

    Looking at most boost gauges

    Vacuum - in.Hg

    Boost (positive pressure) - PSI
     
  17. s3dave

    s3dave TFSI Hybrid
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    It all depends on the calibration of the guages i mean pay 20 quid for a guage you are hardly going to have lab results.....
    Andy123 is correct, it is shown in HG not psi and all the forced induction cars ive had, it has always shown around the 20 in hg mark on idle, infact i used to use this as a tool if it went closer to 10 in hg, i new i had a leak somewhere, and sure enough there was one...:o.k:
     
  18. Dani_B19

    Dani_B19 Audi-sports own special child.

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    Mines around the 20 mark.
     
  19. hades-

    hades- Yorkshire & Humber Rep.
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    -20hg
     
  20. S3 Paul

    S3 Paul Well-Known Member
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    Mine sits at about -18 once warm, Goes up ( or down ) to -22 on over run,
     

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