ECU identification

  • raddy
    raddy
    Member
    • 49
    #1

    ECU identification

    Hi

    Can you help me identify this 300zx z31 ECU:

    label contains:

    A18-688 M50
    there is also big 48 on label
    and also separate 7514

    also, I want to remove resistors in ECU according to this guide for upgrading to Z32 AFM
    http://www.redz31.com/pages/fuel/afmcrap.html

    but inside of ECU looks slightly different compared to picture, I cant find R201.....There are two parallel resistors, which looks like these for remove, but no R201 around.
    Will I still need to remove resistors for Z32 AFM upgrade?

    Thank you for your help
    I need to know if will be
  • bemis
    bemis
    Senior Member
    • 696
    #2
    According to the number, you have a 86 - early87 ECCS. Although these types are programmable, they are nothing like the late87 - 89 models that most people use to modify. In order to make these types programmable, you have to do a couple hardware changes and move around jumpers. I'm not 100% on the details.
    1984 300ZXT
    1986 300ZX 2x2 NA2T
    2000 Porsche Boxster
    2007 Toyota Yaris
  • raddy
    raddy
    Member
    • 49
    #3
    Thanks for reply.

    According to this link
    http://www.tdiclub.nl/topic.asp?TOPIC_I … um_Title=+

    M50 ECU is from japan lambda Z31.

    similar this one:
    http://secretauto.free.fr/page/EPROM/puce_nissan.htm

    so it should be z31 turbo lambda ECU.

    But what is most important for me is If I have to remove any resistors (if yes, which) to make Z32 AFM work with this ECU…
  • bemis
    bemis
    Senior Member
    • 696
    #4
    Well, the fact is, no one has seriously used anything other than a 88 - 89 ECCS as a programmable Z31 unit. So, there isn't any technical data on the older models. I do know that the resistors that you have mentioned are in every Z31 ECCS. They are apart of an OpAmp circuit that brings the Z31 AFM signal into a range that the A/D convertor can read. If you trace the AFM signal through the PC board to an OpAmp, then those resistors used by the OpAmp can be removed, thus creating the same effect as in the 88 -89 units. Finding which resistors to remove from the OpAmp circuitry can be done through a trial/error operation or by looking up the datasheet of the OpAmp and determining which resistors perform the differential effect for the OpAmp.
    1984 300ZXT
    1986 300ZX 2x2 NA2T
    2000 Porsche Boxster
    2007 Toyota Yaris
  • raddy
    raddy
    Member
    • 49
    #5
    Hi
    Im back after some time, while my mate finish assembling his Z31. We have forst serious problem now. Engine can be started, but can rev only to about 2500rpm, then is there some kind of limiter. It is same with disconnected Z32 AFM. Also, engine die with closed throttle.
    Now I can see 2 possible problems:
    1, Z32 AFM itself is broken
    2, ECU is in safe mode becouse of AFM problems

    Regarding to previous post in this topic, I didnt remove resistors in ECU after Z32AFM installing, as I cannot find these resistors in my european ECU version. Can be this source of problem, even with disconnected AFM?

    Thank you
  • Naatgat
    Naatgat
    Member
    • 45
    #6
    Originally posted by raddy View Post
    Hi
    Im back after some time, while my mate finish assembling his Z31. We have forst serious problem now. Engine can be started, but can rev only to about 2500rpm, then is there some kind of limiter. It is same with disconnected Z32 AFM. Also, engine die with closed throttle.
    Now I can see 2 possible problems:
    1, Z32 AFM itself is broken
    2, ECU is in safe mode becouse of AFM problems

    Regarding to previous post in this topic, I didnt remove resistors in ECU after Z32AFM installing, as I cannot find these resistors in my european ECU version. Can be this source of problem, even with disconnected AFM?

    Thank you
    Very, very late reply. I have done this to a euro ecu. Will do writeup soon. You only need to disconnect #14 on op amp board with euro model eccs.