Bringing TBI and Multi Port Fuel Injection to a New Level.     EFI Conversions and Tuning! Seattle to Portland! E-mail Tuning Consultant!
Results 1 to 3 of 3

Thread: Troublecode 51 from ECM at 1980 Firebird

  1. #1
    Carb and Points!
    Join Date
    Jun 2017
    Age
    41
    Posts
    3

    Troublecode 51 from ECM at 1980 Firebird

    Hello at all!

    I have a 1980 Pontiac Firebird Formula with 305cui LG4 "H" engine, Rochester E4ME carburetor, o2-sensor, air pump and c4-system.

    The gas mileage is a little bit high. 16 miles per gallon equals. The spark plugs are very soot-black, the exhaust gases smells at a rich fuel mixture.



    When i check the trouble code, it flashes 5 and 1, therefore it is 51. The GM-manuals says PROM-failure.




    So good i can do, i have controled all the sensors, wires and solenoids, have controled the PROM seat.

    My Problem is, i don't know, is the ECM and the PROM the right for my car. The ECM seems to be refurbished in the past.

    They are lists with numbers, wich ECM and PROM are in wich cars?


    My Numbers are:

    The PROM is an delco 1337 AL, the ECM an 77-4670

    I hope, you can help me to eliminate the failure.

    Bye, Alex

  2. #2
    Fuel Injected! steveo's Avatar
    Join Date
    Aug 2013
    Posts
    2,209
    hey there alex

    a 77-4670 is definitely a "remanufactured" cardone ECM, so it's probably junk.

    get a good used GM one that hasn't been disturbed

    your local auto wreckers probably don't have any, but ebay has lots of new old stock ECMs. part number 1224670, i think

    honestly though your best bet is to either:
    - convert to TBI
    - throw the computer and that rochester in the garbage and just put a normal carb on it

  3. #3
    Carb and Points!
    Join Date
    Jun 2017
    Age
    41
    Posts
    3
    Hello steveo,

    thank you for answer!
    How sure i can be, the PROM 1337AL is the right for my car?

Similar Threads

  1. 7747 in a 1980 Sand rail
    By chadapcb in forum GM EFI Systems
    Replies: 6
    Last Post: 07-04-2016, 11:08 PM
  2. Transmission Troublecode Woes
    By TacticalBacon in forum OBDII Tuning
    Replies: 5
    Last Post: 05-14-2016, 11:13 AM
  3. 1990 Firebird Formula
    By thmprrr in forum Introductions
    Replies: 2
    Last Post: 02-21-2015, 12:17 PM
  4. Hello,my first post 79 firebird
    By Greased-lightning in forum Introductions
    Replies: 9
    Last Post: 01-10-2015, 11:58 AM
  5. Want to convert a 1980 Corolla 1.8 from carb to TBI
    By Dejesusjg in forum GM EFI Systems
    Replies: 21
    Last Post: 06-22-2014, 05:21 AM

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
  •