NEW to myturbodiesel, 2003 Volkswagen Jetta TDi Wagon issues

Discussion in 'VW Mk4 Jetta, Golf, New Beetle, Passat TDI forum' started by Evan_AE86, Nov 2, 2011.

  1. Evan_AE86

    Evan_AE86 New Member

    Joined:
    Nov 2, 2011
    Messages:
    4
    Car:
    2003 Volkswagen Jetta TDi
    Hey my name is Evan and I am from Montreal, Quebc. I am a mechanic apprentice and does a lot of side jobs on friends cars. I joined this site to get more information on VW TDi. I my self own a 1985 Toyota Corolla (AE86). My father on the other hand owns a 2003 Volkswagen Jetta TDi Wagon that he bought new. It is now 8 years old and all of a sudden it needs alot of love and care.

    Recent things that has been done to the car:

    1) a used head was installed because one of the glow plugs had too much carbon build up and could not come out and ended out stripping the threads.

    2) a used injection pump was installed because all of a sudden the car started to stall and the mil light came on with injection pump codes. (I dont remember the code # or how many codes there were)

    3) EGR code P0401 came on all of a sudden and now I was sick of having my dad bring it to mechanics that didnt know the difference between their ass from their elbows and charging him top dollar just because it is a TDI... So I came across this wonderful site www.myturbodiesel.com and was reading everything about the EGR section that someone has made which I have much respect for. So I went to the VW parts place that i know of and bought a new EGR. I took out the old one and it was very clean just oily and all the vacuum diaphragms work perfectly. So I was suspicious about that being the problem. So I did some more research and I came across a forum post of someone saying they got the same code and it ended out being the turbo VNT actuator diaphragm that was leaking. So I ended out buying a vacuum tested and low and behold thats what was leaking. So once I am done writing my first post I am going to go and change that right away.

    I have questions that I will be posting in the appropriate section but right now wish me luck. But it doesn't seem like a hard job so hopefully i can do it under an hour or so. Thank you myturbodiesel.com for this community!

    Evan
    Last edited by a moderator: Nov 3, 2011
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  2. thelike5

    thelike5 New Member

    Joined:
    Nov 2, 2011
    Messages:
    4
    Car:
    VW Jetta 2005.5
    Welcome aboard! I'm new too!
  3. Keithuk

    Keithuk Super Moderator

    Joined:
    Aug 29, 2010
    Messages:
    5,323
    Car:
    2010 Golf GTD (170) CBBB
    Location:
    Stoke on Trent, England
    Welcome to the forum Evan. welcometomyturbodies

    VAG Error Code: 16785
    EOBD II Error Code: P0401

    Fault Location:
    Exhaust gas recirculation (EGR) system - insufficient flow detected

    Possible Cause:
    Hose leak/blockage.
    Basic setting not carried out.
    Exhaust gas recirculation (EGR) valve/solenoid.

    As taken from my http://www.myturbodiesel.com/forum/f9/free-eobd-ii-error-codes-software-2919/
  4. Evan_AE86

    Evan_AE86 New Member

    Joined:
    Nov 2, 2011
    Messages:
    4
    Car:
    2003 Volkswagen Jetta TDi
    Hey everyone!

    keithuk thanks for the info but I narrowed it down to the VNT. There was a leak in the diaphragm for the turbo actuator. I changed it and so far I took it for a test drive and the check engine hasnt came back on yet. I'm going to find out tomorrow when my mom or dad takes the car and does city/highway driving. If the light doesnt come back on then everything is awesome!

    Now I just need to figure out why the hell the car smokes every morning once you turn it on.... Could it be a leaking injector is dripping fuel into the cylinder and then when it starts up it just burns it all and makes alot of smoke???

    The smoke is whitish but not white as presstone and presstone is not going down... and its not blue so I know its not oil.... last idea I have is excess fuel? but its not black....
  5. Keithuk

    Keithuk Super Moderator

    Joined:
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    Messages:
    5,323
    Car:
    2010 Golf GTD (170) CBBB
    Location:
    Stoke on Trent, England
    White smoke on a cold startup normally means insufficient combustion temperature check your glow plugs are operating correctly with a meter not watching when the light goes out?

    A quick test to make sure the glow plugs operate for 20 seconds disconnect the coolant temp sensor and start it.
  6. Evan_AE86

    Evan_AE86 New Member

    Joined:
    Nov 2, 2011
    Messages:
    4
    Car:
    2003 Volkswagen Jetta TDi
    I will try that test with disconnecting the coolant temp sensor and I will post results.

    Also P0401 came back after changing the VNT turbo actuator. Do you know how to test he N75 ? The EGR holds vacuum and is not blocked... Intake has been cleaned. Could the EGR cooler be a possible block up?
  7. Evan_AE86

    Evan_AE86 New Member

    Joined:
    Nov 2, 2011
    Messages:
    4
    Car:
    2003 Volkswagen Jetta TDi
    Alright so I found the problem. For my p0401 code Insufficient EGR flow is caused by the EGR Frequency Valve Actuator (N18). My old one doesn't "click" like the new one does and the vacuum was very weak at the EGR coming from the N18. So I replaced it for $91.25. I will report back if the code comes back but I am sure THAT was the problem. Hope this helps anyone if they find they have a P0401 code also.
  8. 91NCTDI

    91NCTDI New Member

    Joined:
    Oct 20, 2011
    Messages:
    21
    Car:
    2003 Jetta TDI
    Problem solve yet?

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