Idle issues when breaking

Discussion in 'Engine/Drivetrain' started by Tattedfordguy, Dec 31, 2014.

  1. Tattedfordguy

    Tattedfordguy Enthusiast

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    When I step on the breaks for any amount of time the idle starts jumping up and down has anyone had this problem? What do I need to do to fix this!
     
  2. jetas

    jetas Grand Toyotaholic

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    Vaccum leak?
     
  3. White Trash

    White Trash Toyotaholic

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    Yup, either the booster is bad or the vacuum line between the booster and intake is split somewhere.
     
  4. jetas

    jetas Grand Toyotaholic

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    Replace the vaccum to the booster. Its cheap and easy.
     
  5. Tattedfordguy

    Tattedfordguy Enthusiast

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    Can you post a pic of the part
     
  6. jetas

    jetas Grand Toyotaholic

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    The hose coming off of the brake booster. (Not my engine bay BTW)

    [​IMG]
     
  7. Tattedfordguy

    Tattedfordguy Enthusiast

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    Thank you
     
  8. Tattedfordguy

    Tattedfordguy Enthusiast

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    I took it to a shop and they told me it's the part circled, the shop quoted 190 for part
     

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  9. Xs5875

    Xs5875 Addict

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    The afm? No. They are wrong.
     
  10. jetas

    jetas Grand Toyotaholic

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    Thats what im saying
     
  11. tacobo670

    tacobo670 Addict

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    do this. its the simplest easiest fix. if still having issues, most likely its in the booster.
     
  12. B.Y.E.

    B.Y.E. Toyotaholic

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    Sounds more like your idle is set too high. When you apply the brakes the ecu thinks your coming to a stop so it kills the injectors to save fuel. The shops guess at the AFM is the reason for my diagnosis... Base idle is 750-800 rpms, 900-1k with AC on...

    My experience with boosters is a hard pedal feel prior to any idle fluctuation. Good luck!
     
  13. Malandrin4o8

    Malandrin4o8 Newbie

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    Had a similar problem, mine was idle screw came loose on tb turned it down and it stopped it. Might want to check screw.
     
  14. Xs5875

    Xs5875 Addict

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    oh, and its OCD, but this is a huge problem..the title of this thread.

    Your truck has BRAKES. Not BREAKS. You take a break, you use the brakes to stop your truck. Not the other way around....

    ok, rant over.
     
  15. twizted1

    twizted1 Addict

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    rotflmfao!!
     
  16. White Trash

    White Trash Toyotaholic

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    You're right about the idle setting causing the surge too. It's been so long since I dinked with an re I'd forgotten that cause. I've had booster vacuum lines and a vacuum check valve go bad once and the only symptom was rpm surge under braking. It doesn't take much of a leak to cause it.
     
  17. Tattedfordguy

    Tattedfordguy Enthusiast

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    Ha ha, I must have been typing fast and tired sence I work nights...
     
  18. myles66

    myles66 Newbie

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    i had to replace my afm, the electrical chip in it goes out... but you wouldnt be able to keep it running if the afm is out, or at least i wasnt, or anyone else that ive heard of. definitely a vacuum leak and a garage thatll clean up your afm (call it refurbished) and replace youre hose without you being the wiser. or at least thats a what someone as paranoid as me would think...
     

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