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

1.9 tdi sport 130 (6spd) 53' Overboost ?

Discussion in 'A4/A4 cabriolet/S4 forum(B6 chassis)' started by mad4audi, Dec 12, 2013.

  1. mad4audi
    Offline

    mad4audi New Member

    Joined:
    Apr 8, 2009
    Messages:
    3
    Likes Received:
    0
    [Dec 12, 2013]
    Is it true these have Variable Vane Turbos ? Forgive me for my ignorance but what are symptoms if overboosting ? I was reading the sticky about common fixes and was interested in the write up about cleaning VNT through EGR exhaust outlet. I noticed the other night during a cold spell after the car was warm that the revs at above 2800 rpm ever so slight delay/sticking when I revved the car whilst idling, or dipping the clutch when driving.Also I sometimes think there's a delay on boost compared to my friends 5 spd identical sport or is it just that the 6spd ratios/gears are taller hence the torque not coming in low down as vicious as hers lol? Or could thus be linked to the Turbo ? Also I do sometimes here the Dump valve (though this is standard no after market mods) throaty noise from turbo after changing gear, is that the actuator ? Or dump valve? Is this noise normal ? Note my vehicle still pulls like a train and will still spin in second gear when 2500 rpm with my foot applied whilst running through the gearsAny thoughts anyone ? Am I experiencing overboosting as a result of the Vanes sticking ?
    #1
  2. Ads

    Ads

    [Sep 21, 2014]

  3. desertstorm
    Online

    desertstorm Well-Known Member

    Joined:
    Nov 21, 2013
    Messages:
    1,048
    Likes Received:
    292
    [Dec 12, 2013]
    The 1.9 PD engines use VNT turbos, pretty much all new diesel cars use a VNT turbo.
    There isn't a dump valve as such. some people fit them after market but they are a complete waste of time on a diesel as regards performance, they just make a noise and dump all the boost.
    The 5 speed and 6 speed gearbox ratios are the same in 1st second and third. The 6 speed gearbox is a close ratio gearbox so 4th in a 6 speed is like 3.5 in a 5 speed, 5th is like 4.5 and 6th in a 6 speed box is pretty much the same as 5th in a 5 speed.
    If the car was overboosting it would be going into limp mode.
    If you had VAG-COM you could do some data logging and see whats going on.
    You may have a small boost leak on one of the hoses check the joints to see if there is any oil mist. The seals can be replaced with an upgraded green item from the dealers.

    Karl.
    #2

Share This Page