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Thread: L31 Bench harness.

  1. #1
    Carb and Points!
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    Smile L31 Bench harness.

    Hey guys


    A little new to the forum but I need some help. So I got a PCM and a wiring harness from a 1998 Tahoe and I want to reprogram it. Ive seen bench harnesses online for LS1's and stuff but how do you make one for the vortec style pcms with the four connectors? any recommendations?

    thanks

  2. #2
    Fuel Injected!
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    Quote Originally Posted by 85ChevyC20 View Post
    Hey guys


    A little new to the forum but I need some help. So I got a PCM and a wiring harness from a 1998 Tahoe and I want to reprogram it. Ive seen bench harnesses online for LS1's and stuff but how do you make one for the vortec style pcms with the four connectors? any recommendations?

    thanks
    LT1 swap page for the wiring diagram. Need power and ground as well as serial data. From memory only uses one of the 4 connectors to flash it. I have one I made years ago but have not used it in several years. My L31 based engine runs on a 2005 Blue/Green 1 meg PCM.

  3. #3
    Carb and Points!
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    wow thanks! do you possible have the link to the page? im dumb and cant find it xD

  4. #4
    Fuel Injected!
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    lt1swap.com

  5. #5
    Super Moderator dave w's Avatar
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    The attached document was sourced from the Free Version of EFI Live V7.5

    dave w
    Attached Files Attached Files

  6. #6
    Carb and Points!
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    Thankyou very mcuh

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