Results 1 to 7 of 7

Thread: M54 Catalyst problem

  1. #1
    Join Date
    Apr 2019
    Location
    Ny
    Posts
    11
    My Cars
    C43, RX7

    M54 Catalyst problem

    Just got my project '03 530i working well enough to drive. After completing the drive cycle to enable all readiness lights, the cel comes on. This time its p0420 and p0430. Scanning it with inpa shows errors 245,246, 233,234. It looks like there may be a problem with the secondary air system too.

    From what I know these are independent problems? Efficiency is evaluated at 2k rpm at highway speeds and the air system is evaluated at idle and is only used at start up.

    The car has 212k miles on it. I replaced the o2 sensors with used ones that have about 110k on them. I also replaced the maf with a used one that had been recently purchased. The engine runs slightly rough at start up and then has a very faint vibration at idle when warm (no idea what's normal on these cars). Short term fuel trims are 5.5 and 6.3 for banks one and two. Long term is -0.8 and 0.

    I can post o2 data if anyone wants to see. I'm hoping the cats are fine and it's a problem with something else.

  2. #2
    Join Date
    Apr 2019
    Location
    Ny
    Posts
    11
    My Cars
    C43, RX7
    Not sure what inpa code items are so here's the output on two of them.

    233 catalyst efficience Main cat. Bank 1
    N_32 2432 rpm
    MAF 185.20 mg/stk
    TCO 91.50 Grad C
    TIA 32.69 Grad C
    aufetreten vor (rel. BZ) 4.10 h
    catalyst efficience to small
    ---
    ---
    ---
    Error to relevant
    Error debounce
    Error currently available
    Stat. Error
    Errorcode: E9 71 01 28 4C 22 BA 6C C7 A3

    The other code is for bank 2

    Upon inspecting the secondary air valve I realized I had disconnected the hose previously to inspect it and had run it for a minute disconnected causing that error. Basically the secondary air errors are irrelevant to my problem and should be ignored.

  3. #3
    Join Date
    Aug 2014
    Location
    Cheshire, CT
    Posts
    812
    My Cars
    1998 BMW 528i / 5
    I've gotten those codes 3 times, and new pre-cat O2 sensors resolved the problem. First time was at about 100k miles, got codes for both banks. Second at around 180k miles was for only one of the banks. If you're due for oxygen sensors anyway, might want to give it a try.
    Ed CT
    1998 528i
    5-Speed
    Aspen Silver
    Aubergine Leather

  4. #4
    Join Date
    Apr 2019
    Location
    Ny
    Posts
    11
    My Cars
    C43, RX7
    New upstream o2's didnt make a difference. Pulled them out today. Bank 1 is destroyed. Theres a big piece missing and its melted. Bank 2 looks clogged. Must be from the previous owner running it way rich.
    Has anyone had luck welding in aftermarket cats?
    WIN_20190517_11_12_15_Pro.jpgWIN_20190517_11_16_40_Pro.jpg

  5. #5
    Join Date
    Aug 2014
    Location
    Cheshire, CT
    Posts
    812
    My Cars
    1998 BMW 528i / 5
    Well, that sux. From what I remember reading, not all aftermarkets will work with this E39 system. Maybe someone will chime in with their aftermarket experience. You might find some info on viable aftermarkets in a board search here, too.
    Ed CT
    1998 528i
    5-Speed
    Aspen Silver
    Aubergine Leather

  6. #6
    Join Date
    Oct 2010
    Location
    San Jose, CA
    Posts
    10,443
    My Cars
    1997 BMW 540i 6 speed
    I have CA-approved Magnaflows on my car. So far, so good.


    Ed in San Jose '97 540i 6 speed aspensilber over aubergine leather. Build date 3/97. Golden Gate Chapter BMW CCA Nr 62319.

  7. #7
    Join Date
    Apr 2019
    Location
    Ny
    Posts
    11
    My Cars
    C43, RX7
    Did you use the complete header or the weld in?

Similar Threads

  1. M54 hesitation problem.
    By BlAcKrEiN in forum 1996 - 2003 (E39)
    Replies: 8
    Last Post: 11-12-2016, 09:48 PM
  2. Help needed M54 Engine Problem on 2006 E83 with DTC 2882, 2883, 2774, 276D
    By gdking32 in forum 2003+ X3, X4 (E83, F25, F26, G02)
    Replies: 3
    Last Post: 03-19-2016, 02:41 PM
  3. e39 m54 strange problem
    By tianmi in forum 1996 - 2003 (E39)
    Replies: 4
    Last Post: 09-16-2009, 08:14 PM
  4. Catalyst problem
    By thunderbird815 in forum General BMW Mechanical Help sponsored by RM European Auto Parts
    Replies: 0
    Last Post: 06-03-2009, 06:43 AM
  5. Catalyst problem
    By malakia12 in forum Forced Induction
    Replies: 5
    Last Post: 04-07-2005, 09:04 PM

Bookmarks

Posting Permissions

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