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Mystery wires dangling on Mystery Vac Hose

Discussion in 'Electrical & Audio' started by BBBURB, Jun 26, 2019.

  1. BBBURB

    BBBURB Junior Member

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    Hi guys Im a newb and just trying to figure out where these suckers go.

    Do I even need these? Seems after the TBI kit rebuild and new injectors Im running a lot better. I want to throw down some timing on this mother but Im worried about these hanger-ons. What are they?

    If anyone could help identify these suckers or post a diagram for me it'd much appreciated!

    Thanks yall!

    This is a 454 TBI 7.4L

    #1 Wire end has been cut off by a monkey obviously and wrapped in electrical tape!

    454-photo.jpg
     
    Last edited: Jun 26, 2019
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  2. Rusty Nail

    Rusty Nail Build the wall - deport them all! Supporting Member

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    Nice job with the outlines, Slick.
    That looks like a really great, pic. :waytogo:
     
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  3. BBBURB

    BBBURB Junior Member

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    Thank you Rusty, I made it photoshop cc. Took me about 15 minutes. I work with photoshop professionally for many years. Might take an inexperienced user much longer unfortunately.
     
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  4. Snoots

    Snoots Supporting Member Supporting Member

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  5. BBBURB

    BBBURB Junior Member

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  6. Snoots

    Snoots Supporting Member Supporting Member

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    Before I get too excited, let me know if that helps you any.
     
  7. BBBURB

    BBBURB Junior Member

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    I converted those electrical wiring diagrams into a more user friendly pdf file. Now im going to take a deeper look.... Thank you! Will reply back in a moment....

    Link to Wiring Diagram in pdf: https://drive.google.com/file/d/1c1J4-rEokxIAuhE103kFF1xWG3qpXjni/view?usp=sharing


    Ok so I was able to identify this:

    #3 is a tachometer wire which I do not have a tachometer so it would make sense that the wire is not connected to anything. This wire is coming from the coil.
     
    Last edited: Jun 26, 2019
  8. Snoots

    Snoots Supporting Member Supporting Member

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    #5 looks like a check valve feed for the cruise control. Maybe to the brake?
    #6 looks like a PCV hose. That would go to the air cleaner.

    I don't know about the #2 wire from the gray relay. I think the black relay next to it is for the fuel pump or, if you have 2 fuel tanks, the tank switch relay.
     
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  9. bucket

    bucket Super Moderator Staff Member

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    I'm guessing #2 is the test wire for the fuel pump.
     
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  10. Snoots

    Snoots Supporting Member Supporting Member

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    DAMMIT bucket!

    You didn't tell me there was going to be a test?! b4cdb2ebcaaadc3304577c2c3820bcc14046d1191ffceeeebab5578121bb36bb.gif
     
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  11. BBBURB

    BBBURB Junior Member

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    Well after much research I have come to the conclusion that these dingleberry wires are simply there for entertainment and serve no real purpose other than a practical joke at my expense. Thank you all for your help. Let me know if anyone wants some photoshop done!
     
  12. BBBURB

    BBBURB Junior Member

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    Here is what I have so far...

    1. unkown
    2. test wire for fuel pump
    3. tachometer wire
    4. unkown
    5. check valve feed for the cruise control? Maybe to the brake?
    6. plastic pcv hose to air cleaner(changed mine for a rubber hose and a plastic elbow)
     
  13. bucket

    bucket Super Moderator Staff Member

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    As for #1 and #4, green wires of that size and connector style are usually A/C related.
     
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  14. skysurfer

    skysurfer Full Access Member

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    +1. Just checked mine and it's not connected to anything.

    For #5 it's a bit complicated but this should help.

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    So hose 3 terminates at the manifold between the egr and dizzy. Hose 4 goes to the vacuum reservoir. Hose 5 reduces in size just after the junction and goes through the firewall near the ac box.
     
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  15. bucket

    bucket Super Moderator Staff Member

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    Your first two pictures show the mystery green wire plugged in. Where does it go to on your truck?
     
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