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

Misfire on cold starts

Discussion in 'Gen 3 Prius Technical Discussion' started by Rob_Prius, May 28, 2018.

  1. Rob_Prius

    Rob_Prius New Member

    Joined:
    May 28, 2018
    1
    0
    0
    Location:
    Texas
    Vehicle:
    2010 Prius
    Model:
    Four
    Hi there!

    I’m a 2010 Prius owner... and have loved almost every mile I’ve put on this car. I’m near the 200k mark at this point. I’m now starting to have some issues, when my car has been trouble free it’s entire life. On cold starts, I’m now getting a misfire on cylinder one. Thus far, I’ve changed plug, coils, clean my TB, and my EGR is pretty new. Any other areas, I should be looking at, in an effort to resolve this? I did buy new injectors, which I plan on trying next.

    Thoughts?

    Thank you!

    Rob
     
    #1 Rob_Prius, May 28, 2018
  2. mjoo

    mjoo Senior Member

    Joined:
    Nov 9, 2016
    1,107
    1,311
    12
    Location:
    Michigan
    Vehicle:
    2010 Prius
    Model:
    III
    I would read about the oil catch can, EGR system cleaning and head gaskets in the Gen 3 maintenance section of the forum. The engine has an ugly flaw that produces head gasket problems. IMHO it's preventable to some degree with the aforementioned steps.

    Pixel XL ?
     
    #2 mjoo, May 29, 2018
    Last edited: May 29, 2018
  3. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

    Joined:
    May 12, 2018
    6,838
    6,483
    1
    Location:
    Pennsylvania
    Vehicle:
    2018 Prius c
    Model:
    Two
    Have you looked for a vac leak? Maybe flow a little cold propane near the intake flange and injector seal and see if the misfire momentarily goes away.
     
    #3 Leadfoot J. McCoalroller, May 29, 2018
  4. padroo

    padroo Senior Member

    Joined:
    Jan 11, 2008
    2,763
    2,250
    13
    Location:
    Chesterton, Indiana Another third world country.
    Vehicle:
    2016 Prius
    Model:
    Four

    Some vacuum leaks only happen with a cold engine and actually go away with the expansion of the engine as it watts up.

    You could do a cylinder leak down test to verify cylinder integrity.
     
    #4 padroo, May 29, 2018
  5. Blurredforlife

    Blurredforlife Junior Member

    Joined:
    May 10, 2020
    71
    20
    0
    Location:
    Chicago
    Vehicle:
    2012 Prius
    Model:
    Four
    The dealership downloaded an update that seems to have solved this problem for me
     
    #5 Blurredforlife, Mar 15, 2021
  6. Radiospank

    Radiospank Member

    Joined:
    Mar 21, 2013
    152
    70
    0
    Vehicle:
    2010 Prius
    Model:
    III
    is there a way to see which updates you have?
     
    #6 Radiospank, Mar 15, 2021
(You must log in or sign up to post here.)