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

2010 toyota prius cylinder number 4 indentification

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by tjohnson329, Feb 17, 2023.

  1. tjohnson329

    tjohnson329 New Member

    Joined:
    Feb 17, 2023
    8
    1
    0
    Location:
    New York
    Vehicle:
    2010 Prius
    Model:
    I
    I have a 2010 toyota prius with a P0304 cylinder 4 missfire. I have read the thread and looking to troubleshoot but I dont know which one is cylinder 4. any help would be appreciated.
     
  2. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    10,384
    1,794
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    Stand on the right side of the car with the hood up You're looking straight down at the front of your engine at this point The number one spark plug is the closest to your body number two three and four are right behind so the number for spark plug when you're sitting in the car would be the one closest to your probably right knee so if you're standing in the front of the car It would be the last spark plug on the left closest to the driver the one on the far right closest to the passenger is number one
     
  3. mjoo

    mjoo Senior Member

    Joined:
    Nov 9, 2016
    1,134
    1,324
    12
    Location:
    Michigan
    Vehicle:
    2010 Prius
    Model:
    III
    Cylinder #1 is closest to the front of the engine. The front of the engine has the harmonic balancer and accessories (water pump, etc). The rear of the engine is connected to the transmission.

    Cylinders are numbered in ascending order starting from the front to the rear.
     
  4. Mendel Leisk

    Mendel Leisk EGR Fanatic

    Joined:
    Oct 17, 2010
    56,686
    39,234
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    What's the miles on it? Has the EGR system ever been cleaned?

    Cylinder numbering:

    upload_2023-2-17_9-8-5.png
     
  5. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,156
    50,059
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    Same poster with the bad egr
     
    Mendel Leisk likes this.
  6. Mendel Leisk

    Mendel Leisk EGR Fanatic

    Joined:
    Oct 17, 2010
    56,686
    39,234
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Ah, the ol' double thread trick.