82 half the time starts and dies

Discussion in 'Engine: Repairs and Modifications & generally corv' started by monsolo2, May 5, 2015.

  1. monsolo2

    monsolo2 Member

    Guys, I'm helping a friend of mine fix a problem with his 82 L83 crossfire system. Half the time she fires up and runs perfectly... half the time she fires up and then dies and won't start for a little while. Finally, she'll start very roughly and then run fine. I know those had a rudimentary ECM... does anyone know what the starting sequence is or maybe what sensors and solenoids are used? Has anyone else had this problem?
     
  2. grumpyvette

    grumpyvette Administrator Staff Member

    http://garage.grumpysperformance.co...sfire-vette-won-t-run-right.10096/#post-39656

    http://garage.grumpysperformance.com/index.php?threads/got-a-cross-fire-corvette.640/#post-25768

    http://garage.grumpysperformance.co...ng-tpi-crossfire-or-lt1-vette.1401/#post-9259

    http://garage.grumpysperformance.com/index.php?threads/c4-c5-corvette-trouble-codes.2697/#post-7017

    https://www.physicsforums.com/threads/current-draw-of-a-motor-under-different-situations.585336/

    ctrical.com/electricaltech/howitworks.shtml


    the symptoms sound like a defective sensor or fuel pump or fuel pump relay, but read through the links it will prove useful.
    as is true with many questions here theres a few related threads that may hold the answer your looking for in the links and sub links

    I bought a relay, but I don't know how to hook it up. all I see are a few weird numbers and strange symbols, what do they mean?
    -a standard bosch-style relay will have 4 or 5 numbered leads (30, 85, 86, 87, and sometimes 87a). why they picked those numbers, I have no clue; but I can tell what they hook up to.

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    • Lead color code
    • Black: Coil supply
    • White: Coil supply
    • Red: SPDT normally open
    • Blue: SPDT common
    • Yellow: SPDT normally closed
    -30 = constant [positive (+)] power (usually wired directly to car battery)
    -85 = coil ground (wired to the negative (-) battery terminal or any grounded metal panel in the car)
    -86 = coil power (wired to the control source. could be a switch, or it could be the car's IGN or ACC circuit.)
    -87 = switched [positive (+)] power output. (when the relay coil is powered, lead/pin 87 is connected to lead/pin 30)
    -87a = [on 5 lead/pin relays only] this lead/pin is connected to lead/pin 30 when the coil is NOT powered.


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    Last edited by a moderator: Jun 25, 2015
  3. monsolo2

    monsolo2 Member

    Thanks, Grumpy!
     

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