Close

Results 1 to 7 of 7
  1. #1
    Join Date
    Jul 2014
    Location
    Houston
    Posts
    41
    Rep Points
    70.9
    Mentioned
    1 Post(s)
    Rep Power
    0


    Yes Reputation No

    Rough idle after new plugs and JB4 boost question

    So I installed my JB4 a couple weeks ago; after taking it for the first spin I noticed I would get a CEL and/or SES light if I take it over about 10psi of boost. Also after I would get the code it would have a very rough idle. I read the code and it was for a cylinder 1 misfire, figured due to the spark plugs since they were due for a change. But it would only idle rough or throw codes after I would push more than 10psi of boost.

    A couple days ago I went ahead and changed all 6 of the spark plugs and cleaned out the ignition coils, put the car back together and fired it up. The car was idling around 600rpms and it was very rough, the car was shaking and vibrating all over. Figured maybe it just needed to adjust so I took it for a spin, warmed up the engine and then let it rip. No CEL or SES after hitting 15psi of boost or so, so I kept driving it around and got it up to about 18psi of boost and still no issues. No issues while driving or moving, the only issues are when its idling below 1k rpms.

    What could this be? I don't think it has anything to do with the JB4. Was thinking maybe spark plug gaps but they come pregapped and the ECU on the N54 is very good at adapting, so I'm not thinking that's what it is.

    Also, I bought my JB4 used; in first and second gear I can only get about 14psi or so but when I get to third gear and on I can get 18+psi. Could it be that the JB4 was limited in the first two gears by the previous owner?
    E90 335i - JB4 | DCI
    E60 535i - Sport Pkg
    07 Rx-8 - Catless MP, Tuned, Sway Bars
    BMW Performance Parts

  2. #2
    Join Date
    Oct 2011
    Location
    NY
    Posts
    1,962
    Rep Points
    2,657.4
    Mentioned
    49 Post(s)
    Rep Power
    27


    Yes Reputation No
    I would check to make sure all your coil pack connectors are fully secure and pushed all the way up as far they can go. That could cause your issue or maybe one of your plugs are not gapped correctly.
    09 6AT 335i Coupe M-Sport - SOLD
    Current - 16 Jeep Wrangler - Few Mods
    Looking for a n54 project e90/e82

  3. #3
    Join Date
    Nov 2009
    Location
    Simi Valley, CA
    Posts
    8,216
    Rep Points
    9,354.1
    Mentioned
    654 Post(s)
    Rep Power
    94


    Yes Reputation No
    For any JB4 info start reading here. I hope you're not running 18psi on pump gas.

    http://www.n54tech.com/forums/showthread.php?t=10605
    Burger Motorsports
    Home of the Worlds fastest N20s, N54s, N55s, N63s, S55s, and S63s!

    It is the sole responsibility of the purchaser and installer of any BMS part to employ the correct installation techniques required to ensure the proper operation of BMS parts, and BMS disclaims any and all liability for any part failure due to improper installation or use. It is the sole responsibility of the customer to verify that the use of their vehicle and items purchased comply with federal, state and local regulations. BMS claims no legal federal, state or local certification concerning pollution controlled motor vehicles or mandated emissions requirements. BMS products labeled for use only in competition racing vehicles may only be used on competition racing vehicles operated exclusively on a closed course in conjunction with a sanctioned racing event, in accordance with all federal and state laws, and may never be operated on public roads/highways. Please see http://www.burgertuning.com/emissions_info.html for more information on legal requirements related to use of BMS parts.

  4. #4
    Join Date
    Jul 2014
    Location
    Houston
    Posts
    41
    Rep Points
    70.9
    Mentioned
    1 Post(s)
    Rep Power
    0



    Yes Reputation No
    The coil packs are fully pushed down and connectors are fully connected, checked this twice as I had to keep taking it all apart again to try and figure out what was up.

    Also, I've just been running map 5. Cant tell the exact psi but I would guess it to be around 17-18psi while on pump gas.
    E90 335i - JB4 | DCI
    E60 535i - Sport Pkg
    07 Rx-8 - Catless MP, Tuned, Sway Bars
    BMW Performance Parts

  5. #5
    Join Date
    Nov 2009
    Location
    Simi Valley, CA
    Posts
    8,216
    Rep Points
    9,354.1
    Mentioned
    654 Post(s)
    Rep Power
    94


    Yes Reputation No
    You'd want to do datalogs and then post those on the n54tech support forum if you need advice on that end. Won't be much help with the misfires though. Just follow normal troubleshooting for those.
    Burger Motorsports
    Home of the Worlds fastest N20s, N54s, N55s, N63s, S55s, and S63s!

    It is the sole responsibility of the purchaser and installer of any BMS part to employ the correct installation techniques required to ensure the proper operation of BMS parts, and BMS disclaims any and all liability for any part failure due to improper installation or use. It is the sole responsibility of the customer to verify that the use of their vehicle and items purchased comply with federal, state and local regulations. BMS claims no legal federal, state or local certification concerning pollution controlled motor vehicles or mandated emissions requirements. BMS products labeled for use only in competition racing vehicles may only be used on competition racing vehicles operated exclusively on a closed course in conjunction with a sanctioned racing event, in accordance with all federal and state laws, and may never be operated on public roads/highways. Please see http://www.burgertuning.com/emissions_info.html for more information on legal requirements related to use of BMS parts.

  6. #6
    Join Date
    Jul 2014
    Location
    Houston
    Posts
    41
    Rep Points
    70.9
    Mentioned
    1 Post(s)
    Rep Power
    0



    Yes Reputation No
    Where is the software that needs to be downloaded for the data logging? I will try to run some logs and see how it is running.

    Once I feel like stripping the engine bay all down again I will check the gap on the plugs and see if that is causing the issue although I don't think it is the issue. Will also make sure I completely push the coils down and tighten them.
    E90 335i - JB4 | DCI
    E60 535i - Sport Pkg
    07 Rx-8 - Catless MP, Tuned, Sway Bars
    BMW Performance Parts

  7. #7
    Join Date
    Nov 2009
    Location
    Simi Valley, CA
    Posts
    8,216
    Rep Points
    9,354.1
    Mentioned
    654 Post(s)
    Rep Power
    94


    Yes Reputation No
    It's in the link above.
    Burger Motorsports
    Home of the Worlds fastest N20s, N54s, N55s, N63s, S55s, and S63s!

    It is the sole responsibility of the purchaser and installer of any BMS part to employ the correct installation techniques required to ensure the proper operation of BMS parts, and BMS disclaims any and all liability for any part failure due to improper installation or use. It is the sole responsibility of the customer to verify that the use of their vehicle and items purchased comply with federal, state and local regulations. BMS claims no legal federal, state or local certification concerning pollution controlled motor vehicles or mandated emissions requirements. BMS products labeled for use only in competition racing vehicles may only be used on competition racing vehicles operated exclusively on a closed course in conjunction with a sanctioned racing event, in accordance with all federal and state laws, and may never be operated on public roads/highways. Please see http://www.burgertuning.com/emissions_info.html for more information on legal requirements related to use of BMS parts.

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
  •