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HELP: broken throttle body stud

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by waldox, Sep 30, 2021.

  1. waldox

    waldox Junior Member

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    i was cleaning my intake manifold egr ports and installing an oil catch can
    upon reinstalling the rusty bolts and nuts one of the of the intake manifold studs (upper right stud, using 15 ftlbs of torque spec'ed)

    seems like its running fine no leaks. any way to replace the stud or is it welded onto throttle body?

    should i just leave it like that if there are no leaks? (normal fuel trims)
    throttle body.jpg
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    Seems like something missing above; I've added/revised the red. Is that what you meant?

    Regarding the torque values:

    For the two bolts and two nuts holding down the throttle body, the torque is 7 foot/pounds. The studs are 44 inch/pounds (a shade under 4 foot/pounds). I'd acquire a 1/4" drive torque wrench if you don't have.

    The studs screw into thread inserts bonded into the plastic of the intake manifold. Typically they're installed/removed with an E6 Torx socket. Torque the aforementioned 44 inch/pounds.

    Repair Manual excerpt (showing intake manifold and torque values) attached:
     
  3. ChapmanF

    ChapmanF Senior Member

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    Goodness gracious, are you sure? Those throttle body studs and bolts don't look nearly that big.

    My manual says seven foot pounds (ten newton meters).

    tb.png

    If you take the throttle body back off, if you're lucky, some of that stud is still poking up, you can grab it with vise grips and unscrew it, and replace it with a new one (or just use a bolt from the top there; I've never been sure why they did the two bolts / two studs thing).
     
  4. TMR-JWAP

    TMR-JWAP Senior Member

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    I must be having eye problems. It looks to me like there's a nut on that stud...........maybe it's just the piece of stud that normally protrudes a bit, that snapped off? Were the studs/nuts removed as an assembly and installed using the torx on the top of the stud? or were the nuts removed using a deep socket, leaving the stud installed in the manifold??

    If it's just the top portion of the stud that broke off, I'd leave it alone till next time..
     
  5. Mendel Leisk

    Mendel Leisk Senior Member

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    Thing is too, if you remove the studs, then you can get "creative" reinstalling them.Common sense says to install them diagnonally opposite each other, and does it matter which direction diagonal. Give your head a shake: doesn't matter.
     
  6. TMR-JWAP

    TMR-JWAP Senior Member

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    Also, if it is just the top portion of the stud that broke off, it's super simple to remove at next opportunity if desired. Just remove the nuts and the bolts, remove the throttle body and double nut the broken stud. Then all you have to do is use a wrench on the inner nut to back the stud out.
     
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  7. OptimusPriustus

    OptimusPriustus Active Member

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    Probably speeds up assembly a little. One can just drop the body and it aligns perfectly by itself and gasket get no massage. They have lot of little things everywhere. Like those marker dots seen in the picture. We’re talking about one of the most efficient car manufacturers out there, if not the most efficient
     
    #7 OptimusPriustus, Oct 21, 2021
    Last edited: Oct 21, 2021
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