How did my Cutlass even run?

Discussion in 'Electrical' started by Algershick, Mar 19, 2017.

  1. Algershick

    Algershick Greasemonkey

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    I've detailed some of the issues I found with my 85 Cutlass in other threads. Here are a few examples of what I've encountered. Air tubes not connected to anything, catalytic converter port not connected under the car, unplugged CCC harness, secondary choke plates removed, etc etc etc.
    I rebuilt a non CCC qjet, and installed a matching distributor. This morning, I discovered something that I wasn't expecting. I was attempting to remove the ecm wiring harness and found.... There was no ecm. How was it possible for the car to run? Is the advance all that's controlled by the computer as far as ignition goes?
     
  2. oxide80

    oxide80 Greasemonkey

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    Mine was missing the ecu fuse and AIR pump when I bought it. Timing advance didn't work right and the trans lock up wasn't working besides that ran ok, still had the CCC carb, ecu, and correct trans.
     
  3. pagrunt

    pagrunt Royal Smart Person

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    I dumped my ECU after it failed & started to short out my #39 circuit. The old 229 ran better & cleaner than when it was in & working.
     
  4. olds307 and 403

    olds307 and 403 Comic Book Super Hero

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    Good Lord! Usually they go in limp mode but you need an ECM for that. Wow the last owner was obviously a mechanic:(.
     
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  5. Algershick

    Algershick Greasemonkey

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    Wild. If I remember correctly, my 3rd gen F bodies wouldn't even fire without the computer/prom installed.
     
  6. Clone TIE Pilot

    Clone TIE Pilot Royal Smart Person

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    The computer controlled 7 pin HEI modules have a little bit of limp home advance built in. The CCC carb would default to full rich to limp home. Pretty rare for a ECM to fail. Sadly its pretty common for G bodies to have bizarre modifications, Jerry rigging, and butchering by previous owners.
     
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  7. axisg

    axisg Royal Smart Person

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    The CCC system was designed to "dial in" the engine by electronically fine tuning the primary side of the carb and adjusting the timing advance in the distributor. All this in an effort to obtain the optimum 14.7 air to fuel ratio without "knock". Without the ECM it would default to full rich condition and the timing would not advance ( you would also lose the lockup function in the transmission). It would be a little harder to start ( unless you physically moved the distributor to advance the timing ) and it would be very rich but essentially it would run.
     
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  8. Algershick

    Algershick Greasemonkey

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    That answers some questions. It was running super rich when I bought it. The transmission was replaced with a dual pattern TH350 with no lockup, and the kick down cable was hanging down by the shift linkage.
     
  9. L67ss

    L67ss Royal Smart Person

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    Worst rig job on my olds when I got it was the previous owner had installed the most expensive pads you could get at a parts store.....on rotors with grooves so deep they could hide a cigarette. That and a couple taped together plug wires lol
     
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  10. Clone TIE Pilot

    Clone TIE Pilot Royal Smart Person

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    Someone replaced the cap on the overflow tank with a jar's cap in my car.
     
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