I'm at a loss and grabbing at straws...

Discussion in 'Street/strip 400/430/455' started by Brett Slater, Jul 27, 2021.

Page 5 of 8
  1. hugger

    hugger Well-Known Member

    Arching plug wires will in fact do the same,..my turbo Camaro had msd wires with rotted boots drove around fine to be honest,...in boost OR once rpms would come up it would start acting a fool
     
    hugger, Jul 29, 2021
    #81
  2. mygs462

    mygs462 Well-Known Member

    Block the return with a small pair of vice grips n test.
     
    mygs462, Jul 29, 2021
    #82
    DaWildcat likes this.
  3. 69GS430/TKX

    69GS430/TKX Silver Level contributor

    True.
     
    69GS430/TKX, Jul 30, 2021
    #83
  4. redbuick

    redbuick Well-Known Member

    I lost a cam lobe on my 413 after 20k miles, I had similar symptoms.I checked everything prior to that. Good luck
     
    redbuick, Jul 30, 2021
    #84
  5. Lon Bauer

    Lon Bauer Well-Known Member

    On some new plugs I just bought and installed there was a small crack in the porcelain by the terminal that caused a miss fire above 3000 rpm. I went through everything wires, cap, fuel, etc.. until I checked my brand new plugs 1 by 1. Replaced that 1 plug and it was good to go. I'm guessing one of them was dropped at some point causing the slight crack .....
     
    Lon Bauer, Jul 31, 2021
    #85
    Dano, 1972 Stage 1 and Max Damage like this.
  6. 1972 Stage 1

    1972 Stage 1 Well-Known Member

    I agree with Gary. You may need a full 12v to your coil, not the pink resistor wire voltage in your factory harness.

    Ask me how I know! I had the same issue in BG. After a long day at the track with my car cutting out at high RPM’s, we were all re-hydrating with Wild Bill and dozens of his friends when I mentioned this to JW. He told me to try running a full 12 V to the positive side of the coil and make a pass. Problem solved!
     
    1972 Stage 1, Jul 31, 2021
    #86
    Dano and Brett Slater like this.
  7. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    the Lectric ltd unit is supposed to work with the resistor wire in place. Check the coil to see if it has too much resistance. The instructions specify coil primary resistance be 1.3 ohms optimally, but say 1.2 - 1.8 ohms will provide satisfactory performance. I might also try closing the spark plug gaps.
     
    LARRY70GS, Jul 31, 2021
    #87
  8. GSXER

    GSXER Well-Known Member

    Hows the aircleaner? If I use one on a 700hp motor it chokes at 4000rpm
     
    GSXER, Aug 6, 2021
    #88
  9. Brett Slater

    Brett Slater Super Moderator Staff Member

    Update: well, sort of...

    I think I may have unwittingly found my problem: I might have a gremlin somewhere in my year old American Autowire harnesses.

    I had to replace the right front amber bulb last week and the directional worked fine after that.

    I cleaned the car for tomorrow's local BCA show and went for a ride. I noticed that bulb was out again - solid green on the speedo indicator when I pushed the turn signal lever to the right.

    I got back to where I store the car and left it running to adjust the idle up a bit. While it was running, I put the lights on and walked around the car - all the lights were illuminated.

    Like anyone does who's trying to find the bad bulb, I flicked the turn signal lever to check that amber directional: the idle drops and the car dies.

    I did it again with the lights off and the idle dropped again but it didn't die....until I pulled the lights on. Dead.

    More diagnosis forthcoming when I can get it over to my friend's garage.....
     
    Brett Slater, Aug 7, 2021
    #89
    Waterboy, Dano and BYoung like this.
  10. 12lives

    12lives Control the controllable, let the rest go

    It's always something... The good news is, you found a path to go down!
     
    12lives, Aug 7, 2021
    #90
    john.schaefer77 and Brett Slater like this.
  11. 1972 Stage 1

    1972 Stage 1 Well-Known Member

    Did you ever check the voltage going to the coil?

    BTW, the front light harness is a separate harness than the engine harness. It sounds like you are not getting enough voltage to the coil. Alternator is not charging? If that’s the case, it will not like high rpm’s... or low rpm’s with the lights on...
     
    1972 Stage 1, Aug 7, 2021
    #91
    Brett Slater likes this.
  12. Dano

    Dano Platinum Level Contributor

    Not sure if all from the same manufacturer, but this is now the 3rd gremlin I've heard about in brand new harnesses. Repro parts...
     
    Dano, Aug 7, 2021
    #92
    Brett Slater likes this.
  13. steve murray

    steve murray Well-Known Member

    Should prob just burn it !
     
    steve murray, Aug 9, 2021
    #93
    Brett Slater likes this.
  14. Brett Slater

    Brett Slater Super Moderator Staff Member

    Always.
     
    Brett Slater, Aug 9, 2021
    #94
  15. 70 GMuscle

    70 GMuscle Plan B

    E5A79D11-E711-4083-9EDC-9CD75E750E43.jpeg
     
    70 GMuscle, Aug 9, 2021
    #95
  16. 70 GMuscle

    70 GMuscle Plan B

    This is the pin that goes directly into our fuse box on outside. You can make your own 12 guage wire to go directly to coil.
    I also have one from starter to coil for cranking power 12v.
    Let me know if you need one.
    Or on short notice.
    Go to Gm dealer parts dept.
    Tell the parts man you need connector from
    Tray 1
    Bin 2.
     
    70 GMuscle, Aug 9, 2021
    #96
    Brett Slater and Max Damage like this.
  17. Brett Slater

    Brett Slater Super Moderator Staff Member

    Thanks for the picture/input.

    You're about the 4th person to suggest a jumper wire. I wonder if anyone else running the Lectric Limited ignition has had similar issues.

    Kind of negates the "uses stock resistor wire" theory if so...
     
    Brett Slater, Aug 10, 2021
    #97
  18. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    LARRY70GS, Aug 10, 2021
    #98
    john.schaefer77 likes this.
  19. Brett Slater

    Brett Slater Super Moderator Staff Member

    Had a little time to tinker today and seemed to have resolved the directional/stalling issue.

    Cleaned the area on the core support where the ground wires screw in with alcohol and now it's working fine and not dying.

    The other issue still needs addressing. First photo is before start up. Next one is running at high ish idle and the last one is warmed up and idling. Clearly there is a charging issue which is disappointing because this alternator and voltage regulator were rebuilt late last year.

    20210815_085748.jpg 20210815_093639.jpg 20210815_094626.jpg

    I have a known working alternator I'm going to swap pulleys on and try this week.
     
    Brett Slater, Aug 15, 2021
    #99
  20. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    What's wrong with the charging? 12.6 is a fully charged battery, 14.5 volts while running is perfect.
     
    LARRY70GS, Aug 15, 2021
    #100
    Dano likes this.
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