Car boosts what it feels

Discussion in 'N54' started by [email protected], Nov 18, 2016.

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  1. I bought a 1 series off a person that had this setup that was terrible that I reversed. I put a jb4 in at the end of fixing all the others aspects of car. The car now boosts whatever it wants really. Before the fixing it had a turbosmart electronic boost controller and held 20. I put jb4 with a mac solenoid and followed the guide for it. Top port of wastegate to port 2 of mac solenoid and the port 1 side of mac goes to bottom port of wastegate that is tee'd to the compressor housing connection. No matter what I do I get the same results. So I'm lost for words because on the tial chart the biggest spring rate is 21.75.

    Thanks
     
    Last edited: Nov 18, 2016
  2. What are 'the same results'? I'm confused as to what's going wrong?
     
  3. It's free boosting basically, I'm going to replace all the lines to eliminate any other possibilities. If that doesn't work then I'll run compressor nipple to bottom wastegate port to do force wastegate pressure
     
  4. Gotcha. You mean that it's not limiting boost at all. So basically the wastegate is sticking shut.

    Yeah the first step would be to get it to run of wg spring pressure. What spring do you have in there now?
     
  5. That's the problem I don't know, bought the car like this. Car used to have a turbosmart electronic boost controller and held 20 but the setup was no where near ideal. So I will try replacing the lines first. If that doesn't work then I will run force gate pressure. Then if it still does the same thing I'm ordering a new tial MV-R and putting a 12 pound spring in it
     
  6. Tials are rebuildable btw, so you shouldn't need a brand new one if it already has one.

    It should have < a 20psi spring in it. Maybe take a pic of the hose routing? It sounds like zero pressure is getting to the bottom port on the gate. Meaning there's a major leak in the line coming from the compressor and T-ing off to the solenoid and the side WG port.

    You have it routed like this right?
    [​IMG]
     
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  7. Also make sure all the other ports on the gate are capped.
     
  8. Yes it is routed like that, top port of gate to port 2 on the solenoid and port 1 of solenoid to compressor housing and bottom port of gate. I'm going to be replacing the lines. They looked fine to me but maybe something I'm not seeing.
     
  9. 08_335i

    08_335i Sergeant

    271
    2008 ST 335i
    You said you're running jb4, make sure you activated backends (assuming that's what you're running for the single turbo) with menu option 4\2. also make sure you downloaded the single turbo firmware\hex to your jb4. then run a wastegate map (map 1) log and report back.
     
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  10. Everything is set accordingly, tomorrow I'm replacing all the lines. Will report back
     
  11. 08_335i

    08_335i Sergeant

    271
    2008 ST 335i
    Let us know, I'd like to see a log also, that would help show what's going on too.
     
  12. ATL-IS-N54

    ATL-IS-N54 Sergeant

    Sounds like there is more to the POs setup you havnt removed or "reversed" as you said... But what do I know
     
  13. All lines replaced, and car is still doing the same thing. Next trial is to remove top port of wastegate and run bottom port straight to compressor housing and see if it runs wastegate pressure. If not then the wastegate is problematic
     
  14. Not sure what you're implying by this ? Any advice or help is useful
     
  15. Ran compressor nipple straight to bottom port of wastegate and top port disconnected. Same ordeal.


    So bad wastegate ?
     

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