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

Combustion Test ok but still misfiring??

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Levi Gonzalez, Dec 17, 2021.

  1. Levi Gonzalez

    Levi Gonzalez Junior Member

    Joined:
    Sep 19, 2021
    59
    8
    0
    Location:
    Jonesboro AR
    Vehicle:
    2012 Prius
    Model:
    Four
    now currently I have codes for 300 301 302 303 AND 304.

    sound like a head gasket issue?
     
  2. Levi Gonzalez

    Levi Gonzalez Junior Member

    Joined:
    Sep 19, 2021
    59
    8
    0
    Location:
    Jonesboro AR
    Vehicle:
    2012 Prius
    Model:
    Four
    can a PVC or Fuel filter cause misfires?
     
  3. Mendel Leisk

    Mendel Leisk EGR Fanatic

    Joined:
    Oct 17, 2010
    56,688
    39,235
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Did you do leak-down test?
     
  4. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,912
    16,216
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Not so sure about the PCV; fuel filter for sure, if the misfiring is in circumstances of high demand and the fuel delivery can't keep up.

    Have you read the article linked in #16, in particular where it gives you ways of focusing on the conditions when the misfires are most pronounced?