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

Audi S3 boost problems

goodbuzzman1 Mar 24, 2014

  1. goodbuzzman1

    goodbuzzman1 Active Member

    502
    57
    28
    When i picked up my s3 a few weeks ago i knew it would need a bit of work. ive sorted most of the problems but one remains.

    The boost seems to be a bit intermittent.

    so far i have checked for boost leaks. i found that there were leaks in a few breather pipes and also a small leak in the turbo intake pipe.

    I replaced all the offending pipes with nice new silicone ones at the weekend but there till seems to be random hesitance when i put the foot down. sometimes it pulls like a train and other times it stutters and then boosts.

    When i was replacing the TIP, i did notice a slight bit of play in the turbo left to right.

    Ive also been doing a bit of reading about the N75 valve so this evening i unplugged it and went for a spin.

    I have to say, the car felt like it had only 120hp but it was absolutely smooth all through every gear.

    does this mean the valve is good or bad :)

    ANy help on what to do next would be much appreciated

    cheers
     
  2. Vex182

    Vex182 Guess what I drive...

    1,035
    79
    48
    Have you also checked the DV is working as it should? A good idea to check for any fault codes too
     
  3. russwuss

    russwuss Active Member

    549
    106
    43
    If you unplug the N75 you'll be boosting to around 6psi.. Hence why it feels about 120bhp - I'd try swapping the N75 and see if it makes a difference. Was the first thing I had to replace on my S3.
     
  4. russwuss

    russwuss Active Member

    549
    106
    43
    http://bit.ly/1ivqPVG

    ^ that's the one you want, they are more expensive from Audi if
    I remember correctly..
     
  5. goodbuzzman1

    goodbuzzman1 Active Member

    502
    57
    28
    how exactly would i go about testing it
     
  6. goodbuzzman1

    goodbuzzman1 Active Member

    502
    57
    28

    do you think its worth replacing? i might just get one anyway and try it.
     
  7. <tuffty/>

    <tuffty/> Badger 5 Edition...Its all about the flow... Staff Member Moderator Audi S3

    20,878
    3,701
    113
    Have you scanned for fault codes yet?

    <tuffty/>
     
  8. goodbuzzman1

    goodbuzzman1 Active Member

    502
    57
    28
    I will be giving it a scan this evening. I just wanted to repair the obvious boost leaks before i did
     
  9. goodbuzzman1

    goodbuzzman1 Active Member

    502
    57
    28
    Ok. So i scanned the car this evening and it didnt give me any fault codes (apart from one for the radio antenna)

    I tested the diverter valve and that seems to be ok.

    What i did notice was that the pipe that goes from the diverter pipe over to the turbo pipe is suffering from the same heat related collapsing as all the other ones i have just replaced. One of the bends is especially bad and i cant imagine much can flow through it. but how much affect could it have? enough to affect performance?
     

Share This Page