Replacing spark plugs

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by avoice217, Dec 19, 2025.

  1. CR94

    CR94 Senior Member

    Joined:
    Dec 2, 2014
    2,709
    1,178
    0
    Location:
    Northwestern S.C.
    Vehicle:
    2011 Prius
    Model:
    Two
    Couldn't unequal clogging of EGR ports of the manifold be a plausible culprit for "starting to shake while ... accelerating", even if the head gasket is ok?
     
  2. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    27,730
    18,318
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    As I understand things, shakes on initial startup, after sitting for a while, and quickly clearing up, would cast suspicion on the head gasket.

    Shakes while driving, if they are not present at idle and not present at full throttle, but show up at moderate loads when EGR is used, would cast more suspicion on the manifold EGR passages, and wouldn't be very consistent with a head gasket problem.
     
  3. avoice217

    avoice217 Member

    Joined:
    Jul 20, 2022
    175
    22
    0
    Location:
    Texas
    Vehicle:
    2009 Prius
    Model:
    II
    Hey guys, let me put everything back together and take it for a drive. I certainly hope that its not the head gasket, but we shall see. I did notice at least 1 of the small holes clogged inside the intake manifold, so tomorrow I'm going to put the intake manifold back into the car and see how things go. I'm also going to inspect the pcv valve while I have to intake manifold out. I did watch a video on how to interpret the sound on that.
     
  4. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    7,652
    3,939
    0
    Location:
    Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    You might as well replace the pcv valve while it's out. It's $10-15 part. And not fun
    to get it with the intake manifold on.....

     
    Mendel Leisk likes this.
  5. avoice217

    avoice217 Member

    Joined:
    Jul 20, 2022
    175
    22
    0
    Location:
    Texas
    Vehicle:
    2009 Prius
    Model:
    II
    Hey all, so heres the current situation: I'm working on trying to put the car back together. However, there's a few hoses that I'm not sure of the location. I've tried finding pdf's of diagrams regarding the location and can't seem to find them. As soon as I plug all the hoses back into place, then the rest of the car will get put back together.
     

    Attached Files:

  6. avoice217

    avoice217 Member

    Joined:
    Jul 20, 2022
    175
    22
    0
    Location:
    Texas
    Vehicle:
    2009 Prius
    Model:
    II
    Hey all so this is where I am at currently. I've been able to find most of the hose locations. However, I'm having a difficult time finding the hose that goes here.
     

    Attached Files:

  7. indel

    indel Member

    Joined:
    Apr 1, 2024
    194
    73
    1
    Location:
    Northwest Indiana
    Vehicle:
    2012 Prius
    Model:
    Two
    Look for a coolant hose that's hanging unattached.
     
  8. avoice217

    avoice217 Member

    Joined:
    Jul 20, 2022
    175
    22
    0
    Location:
    Texas
    Vehicle:
    2009 Prius
    Model:
    II
    Yes so for the coolant hose thats hanging unattached, unfortunately I can't seem to find where it's supposed to go. I've looked all around and have no idea where it's supposed to go back to. For the metal pipe that doesn't have a hose attached, the only information I have refers to a half part number, which is 16267. Problem there is that there's many Toyota parts with that first half, so that doesn't help.
     
  9. indel

    indel Member

    Joined:
    Apr 1, 2024
    194
    73
    1
    Location:
    Northwest Indiana
    Vehicle:
    2012 Prius
    Model:
    Two
    Can you post a zoom out picture so we can see what the metal tube is attached to? It looks to me like the EGR cooler coolant port. Also, take a look at page#2 of the attached diagram. It might help you figure out what's missing.
     

    Attached Files:

    #49 indel, Jan 13, 2026 at 7:27 PM
    Last edited: Jan 13, 2026 at 7:33 PM
  10. avoice217

    avoice217 Member

    Joined:
    Jul 20, 2022
    175
    22
    0
    Location:
    Texas
    Vehicle:
    2009 Prius
    Model:
    II
    So based on the diagram that you should, its the larger hose coming out of the egr cooler. However, I'm not getting any help from Google on that.
     
  11. indel

    indel Member

    Joined:
    Apr 1, 2024
    194
    73
    1
    Location:
    Northwest Indiana
    Vehicle:
    2012 Prius
    Model:
    Two
    There should be four coolant hoses attached to the cooler. You have one missing. You may have attached it to something else.
     
  12. avoice217

    avoice217 Member

    Joined:
    Jul 20, 2022
    175
    22
    0
    Location:
    Texas
    Vehicle:
    2009 Prius
    Model:
    II
    As you requested, here's zoomed out photos of those areas.
     

    Attached Files:

  13. rjparker

    rjparker Tu Humilde Sirviente

    Joined:
    Jun 6, 2008
    10,243
    6,396
    7
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
  14. avoice217

    avoice217 Member

    Joined:
    Jul 20, 2022
    175
    22
    0
    Location:
    Texas
    Vehicle:
    2009 Prius
    Model:
    II
    Hey rjparker, so I looked it up and found the hose. However, the split at the end I honestly dont remember.
     
  15. avoice217

    avoice217 Member

    Joined:
    Jul 20, 2022
    175
    22
    0
    Location:
    Texas
    Vehicle:
    2009 Prius
    Model:
    II
    Now any ideas where the hose that's connected to the green clamp goes by chance? I've been looking constantly and can't seem to figure out where to put that.
     
  16. rjparker

    rjparker Tu Humilde Sirviente

    Joined:
    Jun 6, 2008
    10,243
    6,396
    7
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    Looks like bottom reservoir hose to radiator

    IMG_0226.jpeg

    IMG_0223.jpeg

    IMG_0224.jpeg
     
    #56 rjparker, Jan 13, 2026 at 9:49 PM
    Last edited: Jan 13, 2026 at 10:11 PM
  17. avoice217

    avoice217 Member

    Joined:
    Jul 20, 2022
    175
    22
    0
    Location:
    Texas
    Vehicle:
    2009 Prius
    Model:
    II
    Hey all, so possibly my last update. So my mom happens to own the same generation model car, so I was able to remove the engine air filter and assembly in order to understand what's going on with my car. It just happened that I moved the house from that area to the left side so that I could get a better understanding of the car and that's how it messed with my head. Needless to say, I was able to move it back to the other side and it fit into that metal pipe.

    So overall, I'm only missing one hose, which connects the purge control solenoid valve to the metal pipe. The good news is that I was able to get the car off the road (which is short term goal). Now I just need to find a possible new hose for that area and then I'm all set. The hose actually busted on me today.

    I would like to apologize to all those that got nervous about my work. In all fairness, there's no places here in Texas where they can teach someone how to work on a car and thus I had to learn it on my own. If I had to do everything again, I definitely would've just ordered a brand new intake manifold (they're sold on eBay for around $90), but I still would've had to deal with that one dumb hose.
     
  18. Mendel Leisk

    Mendel Leisk MMX GEN III

    Joined:
    Oct 17, 2010
    60,504
    41,646
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    You were ostensibly doing an EGR cleaning? The only coolant hoses you needed to touch were the two at the EGR cooler, and just the cooler ends of those.

    the coolant hoses connecting to the throttle body do NOT need to be disconnected: just unbolt the throttle body with hoses, lift it off, tie it to the adjacent inverter conduit.

    Regarding the myriad hose clamps: they’re largely ineffective at preventing spills. A better ploy is to drain 2 quarts of coolant at the outset, at the radiator drain spigot, into a clean container. This leaves the EGR components high and dry. When done, pour it back into the reservoir, while leaving the engine coolant air vent open till coolant starts coming out (model year 2010~2011), or the topmost cooler hose pulled off, for subsequent years that nixed the vent.

    seriously, have a read through the top two links in my signature. (On a phone turn it landscape to see signatures)
     
  19. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    27,730
    18,318
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    The subsequent years dropped that vent, and dropped all instructions about using that vent from the repair manual, and did not add any new instruction to pull any hose off or engage in any other new hocus pocus.

    That sequence of events could lead one to suspect that for 2010-11 there was still somebody on the engineering team unconvinced that their new degas-bottle cooling system would self-purge as designed without the extra valve, and that by 2012 experience had allayed that concern.
     
  20. Mendel Leisk

    Mendel Leisk MMX GEN III

    Joined:
    Oct 17, 2010
    60,504
    41,646
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    I changed both coolant circuits last fall, and when refilling engine coolant, I left that vent open with a clear tube attached, both to keep things tidy and to help spot any coolant. It's at a high point of the circuit. Near the end of the fill coolant started coming out, and once it was a steady flow I closed it off.