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Discussion in 'Leon Mk1 (2000-2006)' started by Redworminator, Nov 11, 2019.

  1. Redworminator

    Redworminator Active Member

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    Have a little issue with my 2001 LC, when I first start it up for the day I seem to have no boost, it drives like a 1.8 n/a. If I turn it off and back on, it drives absolutely fine for the rest of the day regardless of how many times I turn it off and back on again.
    I replaced the DV with the latest OEM one from Seat, no change. I unplugged the MAF but no change, then I replaced the N75 with a like for like, now there is no boost at any time and throws up code 17705, I put the old one back on and once I turn it off and back on drives fine, I can live with this but would be nice to be able to get to the bottom of it, anyone have any ideas?
     
  2. Andrewwright

    Andrewwright Turbo lover

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    Unplugged the MAF but no change??
    MAF is broken.

    Sent from my Nexus 6 using Tapatalk
     
  3. Redworminator

    Redworminator Active Member

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    Do you think? even though I could drive it all day ( as I did on Saturday) on the second start up with no issues? What should happen if you unplug a good MAF? Thanks
     
  4. Andrewwright

    Andrewwright Turbo lover

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    Unplugging a good MAF will result in ruff engine running

    Sent from my Nexus 6 using Tapatalk
     
  5. Alexis27

    Alexis27 Active Member

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    N249 valve is one possibility. Although it rarely fails - it's almost always the accompanying pipe work
     
    #5 Alexis27, Nov 11, 2019
    Last edited: Nov 11, 2019
  6. Redworminator

    Redworminator Active Member

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    Ok I'll get a new MAF and check the pipework, then go from there, I'm a little confused about the N75 though
     
  7. Alexis27

    Alexis27 Active Member

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    What is the code on the new one? And was it a genuine OEM one or a cheap Chinese copy? You can't really get a genuine one for less than £55.
     
  8. Redworminator

    Redworminator Active Member

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    It's the same code as the genuine one I had on it, I got it from just German parts
     
  9. Andrewwright

    Andrewwright Turbo lover

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    Before you do that check it again. There £75+ so have it running, pop the bonnet and unplug it. If no change then yes it's faulty. Smoke test will help no end with air leaks.

    Sent from my Nexus 6 using Tapatalk
     
  10. Redworminator

    Redworminator Active Member

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    Ok great thanks for the advice, I'll give that a go in the morning
     
  11. mty12345

    mty12345 Active Member

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    I very much doubt it is the MAF or infact anything physically wrong with the car at all.

    17705 is a common code caused by a certain parameter that gets over looked when cars are remapped. It usually only shows up in the winter, because it is only triggered when the car is started from 5C or below. When you turn the key off and back on again, the car is now starting from warm so that code won't be triggered again until the next cold start. This is why it only usually does it once a day.

    I have some info somewhere on it somewhere. I will find the link for you later when i get chance. Hold off on the MAF for now mate

    Edit: here you go buddy. https://18t-tuning.co.uk/17705-pressure-drop-between-turbo-and-throttle-valve/
     
    #11 mty12345, Nov 11, 2019
    Last edited: Nov 11, 2019
    Larry Millar likes this.
  12. Redworminator

    Redworminator Active Member

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    Interesting, thanks for that, maybe I don't need to do anything at all
     
  13. mty12345

    mty12345 Active Member

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    Yep, when i first got mine that code drove me crazy for months. If you want to sort it then see if you can find a mapper willing to change the value of the parameter called 'FVPDKLDUS' from whatever the current value is to a '0' instead.

    I've been on here 8 years and problems with this code come up every time the weather gets cold.
     
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  14. Redworminator

    Redworminator Active Member

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    Thanks mate, I don't think I'll bother doing anything I can live with it. And I'd probably guess that the N75 I bought is faulty, I'll just get another or a refund.
     
    mty12345 likes this.
  15. Alexis27

    Alexis27 Active Member

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    Is it remapped?
     
  16. Redworminator

    Redworminator Active Member

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    Well not in my ownership or any receipts from previous owner, but I had it rolling roaded last week and is putting out 188bhp 237lb/ft so thinking yes probably
     
  17. Alexis27

    Alexis27 Active Member

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    Ah, yes the remap that isn't making as much power as it should! Crappy map could be something to do with your fault code
     
  18. Redworminator

    Redworminator Active Member

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    Yeah possibly, I'm happy with how it runs tbh, I'll run it into the ground then get myself a R, it only cost me £700 so wouldn't make sense to spend £400 on a remap to me.
     
    bigT's lcr likes this.

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