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  1. #1

    Default What are these two plugs?

    Could anyone tell me what these two wiring harness plugs are circles in red on the attached photo?

    They are attached to the fire wall above the distributor to the passegner side on TBI 350 suburban.

    What is wierd is they don't go anywhere! I mean, the thing that recieves the plugs doesn't have any wires coming out of it?

    I unplugged these while I was doing some work and forgot which one went on the pass side and which goes on the drivers side. The two recepticals are identical.

    It seems the must be important, being so high up and with all the wires, but it is a mystery to me what they are.

    One plug is grey and the other black, does anyone know which goes into which side? In the photo, it seems grey plug goes on drivers side, but I'd like to confirm before I blow up my freshly rebuilt engine.

    Attached Thumbnails Attached Thumbnails what are these two plugs.JPG  

  2. #2


    I believe those to be relays. If so, one is for the fuel pump and the other is for the transmission downshift. They should be the same relays, so reversing them shouldn't hurt anything.

    99 K 1500 Suburban
    78 Silverado Big 10 w/factory 454
    00 S-10 Blazer
    1976 Trans Am
    1980 Honda CB900 Custom

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