1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Sticky brake pedal

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Tom in Maine, Sep 6, 2017.

Page 1 of 2
  1. Tom in Maine

    Tom in Maine Junior Member

    Joined:
    Mar 14, 2013
    23
    7
    0
    Location:
    Searsport, Maine
    Vehicle:
    2005 Prius
    Model:
    II
    I have a 2010 Prius with 163k on it.
    The brake pedal seems to stick. Once coming to a complete stop, the pedal does not usually retract and the brakes seem to drag until the pedal comes back up.
    I can usually lift the pedal about 1/2" or so to retract it.
    If I lube the pivot points at the pedal, it seems better for a couple uses, but if I brake hard, it comes back.
    I cannot get a clear understanding of any interference from the system like the stroke simulator, if that is in play here.
    Wondering about lubing inside the boot to the master cylinder shaft.

    The braking is fine and there is ample resistance and stopping. The pedal just is sticky and the brakes do drag until the pedal is lifted back or the car moves a bit and it then comes out of this.

    My Former Toyota mechanic friend has not come across this one. Hope someone here has.

    Thanks,
    Tom
     
    #1 Tom in Maine, Sep 6, 2017
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    108,753
    49,412
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    not sure if it comes into play, but might be worth checking your 12v. no dash lights?
     
    #2 bisco, Sep 6, 2017
  3. Tom in Maine

    Tom in Maine Junior Member

    Joined:
    Mar 14, 2013
    23
    7
    0
    Location:
    Searsport, Maine
    Vehicle:
    2005 Prius
    Model:
    II
    No codes, nothing odd. Will double check voltage.
     
    #3 Tom in Maine, Sep 6, 2017
  4. Raytheeagle

    Raytheeagle Senior Member

    Joined:
    Jul 1, 2016
    11,251
    15,481
    0
    Location:
    Bay Area, California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    Original brake pads? Had a servicing done recently? Level of brake fluid in the reservoir?
     
    #4 Raytheeagle, Sep 6, 2017
  5. Tom in Maine

    Tom in Maine Junior Member

    Joined:
    Mar 14, 2013
    23
    7
    0
    Location:
    Searsport, Maine
    Vehicle:
    2005 Prius
    Model:
    II
    Just through the shop for a state inspection. My mechanic loves to spend my money. Nothing overtly wrong needing attention.
     
    #5 Tom in Maine, Sep 6, 2017
  6. Raytheeagle

    Raytheeagle Senior Member

    Joined:
    Jul 1, 2016
    11,251
    15,481
    0
    Location:
    Bay Area, California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    What does a state inspection in Maine consist of? Did you have to have any work done prior to the state inspection? Any history of accidents? Original owner?
     
    #6 Raytheeagle, Sep 6, 2017
  7. Tom in Maine

    Tom in Maine Junior Member

    Joined:
    Mar 14, 2013
    23
    7
    0
    Location:
    Searsport, Maine
    Vehicle:
    2005 Prius
    Model:
    II
    All Brake components. Car is new to me. No history, but nothing obviously repaired. Not a rebuilt title as with a salvage vehicle.
    The only issue is the pedal is not returning to its original position. Once it is retracted everything is okay. I am pretty certain this is
    in the pedal mechanism.
    I sell used Priuses for a living, so I have laid hands on a lot of issues. This one is puzzling.
     
    #7 Tom in Maine, Sep 6, 2017
  8. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    23,891
    15,534
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    What happens if you take out the clevis pin between the brake pedal and the pushrod? When the brake has been pushed and gets stuck, and you pull the pedal back up, does the pushrod follow it back? In other words, is it the pedal binding, or the master cylinder?

    I know I've been skeptical of the 12-volt-battery-as-root-of-all-problems school of thought before, but if bisco can explain how low battery voltage is going to make the brake pedal or master cylinder pushrod physically bind, I might have to admit defeat.

    -Chap
     
    #8 ChapmanF, Sep 6, 2017
    bisco and GrGramps like this.
  9. RMB

    RMB Senior Member

    Joined:
    Jun 21, 2016
    406
    642
    0
    Location:
    Oakland, CA
    Vehicle:
    2014 Prius
    Model:
    Three
    Brake pedal free play? Return spring?
     
    #9 RMB, Sep 7, 2017
  10. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    108,753
    49,412
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    I would, but it's above my pay grade.:cool:
     
    #10 bisco, Sep 7, 2017
    Raytheeagle likes this.
  11. Tom in Maine

    Tom in Maine Junior Member

    Joined:
    Mar 14, 2013
    23
    7
    0
    Location:
    Searsport, Maine
    Vehicle:
    2005 Prius
    Model:
    II
    Had my mechanic give it another go. He lubed the hell out of it but it is still a little sticky.
    I am going to get a slightly beefier return spring. This seems to be the issue. It is now less constant than it was.
    We'll see.
     
    #11 Tom in Maine, Sep 7, 2017
  12. NutzAboutBolts

    NutzAboutBolts Senior Member

    Joined:
    Mar 5, 2013
    1,476
    1,552
    0
    Location:
    Bay Area
    Vehicle:
    2012 Prius
    Model:
    Four
    I would check the caliper pistons to see if its stuck or seized...
     
    #12 NutzAboutBolts, Sep 7, 2017
    bisco likes this.
  13. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    108,753
    49,412
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    agreed, and double check the 12v.;)
     
    #13 bisco, Sep 7, 2017
  14. WoodyGecko

    WoodyGecko New Member

    Joined:
    Sep 15, 2017
    2
    0
    0
    Location:
    Colorado
    Vehicle:
    2004 Prius
    Model:
    II
    Having the same brake pedal issue with my 2004 2nd Gen Prius almost 206k miles.
     
    #14 WoodyGecko, Sep 15, 2017
  15. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    55,475
    38,682
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    I'm wondering too, if it's due to neglected brake maintenance, and the pedal's behavior is just the canary in the coal mine? Not sure though.
     
    #15 Mendel Leisk, Sep 15, 2017
    NutzAboutBolts likes this.
  16. Michael Mann

    Michael Mann Active Member

    Joined:
    May 7, 2015
    165
    408
    0
    Location:
    Bay Area, CA
    Vehicle:
    2010 Prius
    Model:
    III
    Old thread but I’m having the same issue. Spring return looks good, brake fluid, nothing seems to be leaking. This one has me stumped...
     
    #16 Michael Mann, Feb 5, 2018
  17. Tom in Maine

    Tom in Maine Junior Member

    Joined:
    Mar 14, 2013
    23
    7
    0
    Location:
    Searsport, Maine
    Vehicle:
    2005 Prius
    Model:
    II
    We wound up replacing the master cylinder with a used one.
     
    #17 Tom in Maine, Feb 5, 2018
    Michael Mann likes this.
  18. FuelMiser

    FuelMiser Senior Member

    Joined:
    Jun 29, 2008
    1,298
    885
    0
    Location:
    Monument, CO
    Vehicle:
    2016 Prius
    Model:
    Touring
    Thank goodness it wasn't the 12V!
     
    #18 FuelMiser, Feb 6, 2018
  19. Skier

    Skier New Member

    Joined:
    Apr 4, 2019
    2
    0
    0
    Location:
    Boston
    Vehicle:
    2010 Prius
    Model:
    LE
    Hi. So what is the solution? I have the same issue with my 2010. I almost constantly have to pulll the brake pedal back up with my left foot.
     
    #19 Skier, Apr 4, 2019
  20. Skier

    Skier New Member

    Joined:
    Apr 4, 2019
    2
    0
    0
    Location:
    Boston
    Vehicle:
    2010 Prius
    Model:
    LE
    Did this solve the problem?
     
    #20 Skier, Apr 4, 2019
(You must log in or sign up to post here.)
Page 1 of 2