87 Fifth Avenue - Wiring a new electronic ignition

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  1. natman

    natman New Member

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    Hey there. I recently bought an 87 fifth avenue and am in the process of bypassing the dead lean burn system on it. I bought a kit with a vacuum advance distributor, ballast resistor, ECU, and wiring. Unfortunately the instructions that came with this kit isn't very specific about how to wire the start/run wires to the ballast resistor. It vaguely tells you how to find and determine the "run" wire, but hardly mentions the "start" wire and where it is.

    There's a diagram that was included, but again, not much that tells you where to tap those start/run wires into.

    [​IMG]

    I have everything else hooked up at this stage, but am kind of roadblocked here. I tried to find info online about this, but most of what I'm reading is for older models with different wiring setups/colors.

    If anyone has done this conversion with this set up/year and could tell me which wires they tapped into, I would very much appreciate it!
     
  2. kingoftooland

    kingoftooland Member

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  3. natman

    natman New Member

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  4. kingoftooland

    kingoftooland Member

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    keep me posted I should be getting my car back tomarrow
     
  5. natman

    natman New Member

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    Well, I got the battery charged, and so far it's working great! I tapped the "run" wire to the dark blue main ignition feed going into the main wiring harness on the firewall. I then ran the "start" wire to the "bal" terminal on my starter relay (as per the instructions on the link I posted). Before I found that page, I tapped the start wire into the yellow wire on the starter relay, and that was causing the starter to engage with the key in the "on" position, so that definitely wasn't right!

    I'll need to buy or rent a timing light so I can set the timing properly. So far though, she runs A LOT better and my misfiring is gone, so I'm happy with this upgrade.
     
  6. BudW

    BudW Moderator Staff Member

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    I condensed that PDF to make things a little simpler. The power feed (to the new ignition module) needs to connect the bulkhead (firewall) connector pin. Once you find the correct wire, it might be easier to cut that wire a couple of inches away from the bulkhead connector and solder it to your new ignition feed wire. That way there is no power going to the computer.
    Ignition Changeover C.jpg
    This connector is actually under the dash
    Ignition Changeover D 79.jpg

    Ignition Changeover D 80-87.jpg

    Ignition Changeover E.jpg
    The (above) blue colored pin needs red circle (below)
    ECU wiring.jpg

    If you wanted to tie back the old wiring or simply cut it off the (old) computer pigtails – go for it (…within reason), for there will not be any power sent that way anymore.

    One IMPORNTANT step omitted in the instructions (above) is power going to the Choke Thermostat. The Electric Choke Thermostat is tapped into the same 12-volt source going to the ballast resistor (the wire you just tapped into at the bulkhead connector). In many cases, it might be easier to just run a new wire to the Choke Thermostat.
    Note: depending on the year of car was made, the Choke Thermostat feed was either directly fed from ballast resistor or via the engine oil pressure switch (OPS). On cars with a 3-wire OPS, the power to Choke Thermostat would be not present until car was started (to keep from draining the battery for those who insist on listening to radio with car in “ON” instead of “ACC”).

    If you do not connect power to electric choke thermostat, car will not run well until engine gets hot.

    When the distributor is out of car, look at the engine OPS. If it has three wires going to it, like this one:
    Standard PS133.jpg
    Then you might need to run the same power wire the dark blue wire for the oil pressure light (on dash) to work correctly. The gray wire goes to the dash light and the dark blue w/red tracer goes to the choke thermostat.

    This is one example of the single wire OPS:
    Standard PS11T.jpg

    BudW
     
  7. kingoftooland

    kingoftooland Member

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    I’ll have to remember that because this summer I want to clean up the wiring underneath my hood and yes I’ve actually done the Mopar conversion for the electronica ignition because I removed everything they had to deal with my lien burn because it wasn’t even running right it would barely run when I first bought the car right now this is the current rats nest of wiring underneath the hood LOL

    image.jpg

    image.jpg
     
  8. BudW

    BudW Moderator Staff Member

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    I understand the “rats nest”.

    Could you take pictures of the drivers side throttle cable setup (to carburetor) and kickdown linkage setup and post here, please?
    I'm guessing either you or previous owner installed the 4-bbl setup?

    Does your engine oil pressure light work?
    BudW
     
  9. kingoftooland

    kingoftooland Member

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    I’ll try once I get out of work