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

Oil leaks on rear of engine and could it be a Head gasket issue?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by nate358, Mar 29, 2022.

  1. nate358

    nate358 Junior Member

    Joined:
    Feb 25, 2012
    94
    19
    0
    Location:
    Columbus, OH
    Vehicle:
    2006 Prius
    Model:
    N/A
    I have a 2012 Prius v with about 131,000 miles. I’ve been burning oil for awhile but never milky and I used to change the oil annually with about 15k miles between changes… I know the marketing screwed me there. Coolant level was a little low last year and I brought it back up to level. I have no engine codes that have come up. My front wheel bearings have gone bad and while changing them, I screwed up the axels getting the nuts off so I’m putting in all new front suspension and axle. Anyways, I’m also going to clean the EGR system and put in a new PCV valve, but after taking out the passenger axel, I noticed oil leaking from what looks like the crankshaft position sensor, oil pressure sensor, and a third bolt. I did do a block test on the cooling system and it DIDN’T change color. I have gone to every auto parts store to get a tool to do a pressure test on the cooling system and I can’t find an adapter that fits the coolant bottle. I put a bore scope down the spark plug holes and the left and right most cylinders look a little too clean. I uploaded a video to YouTube of the oil leaks… do you think it’s my head gasket blown?

    here is the video of the oil leaks on the back side of the engine above the oil filter housing.

     

    Attached Files:

  2. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    8,920
    1,553
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    But you don't have any stuttering or any of that funny business going on knocking noises and missing type sounds for the most part and if you pull the number two spark plug especially do you see any water droplets on the ceramic part of the plug that's inside the cylinder just below the electric or back up the plug you see any water touch your tongue to it taste like coolant?
     
  3. nate358

    nate358 Junior Member

    Joined:
    Feb 25, 2012
    94
    19
    0
    Location:
    Columbus, OH
    Vehicle:
    2006 Prius
    Model:
    N/A
    No shuddering at start up. Randomly the engine shuts down hard when at a stop light. Cylinder 2 and 3 seem at the top of the stroke so I can’t really get a clear picture. Spark plugs seem discolored but dry. Top is 1, then 2 , 3, and 4 at the bottom in the picture.
     

    Attached Files:

  4. rjparker

    rjparker Tu Humilde Sirviente

    Joined:
    Jun 6, 2008
    7,918
    4,680
    7
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    Oil leaks are often on the timing chain cover. Yours seems to start at the timing chain tensioner which is right at the timing chain cover seal.

    Your borescope pics of a pic are not very good. Check "The Car Care Nut" youtube channel from a few weeks ago where he shows how to do a borescope inspection. May require a better instrument.

     
  5. nate358

    nate358 Junior Member

    Joined:
    Feb 25, 2012
    94
    19
    0
    Location:
    Columbus, OH
    Vehicle:
    2006 Prius
    Model:
    N/A
    yes, I watched that and wish I had his borescope… the ones I can rent don’t turn to the side and the mirror that comes with it can’t fit in the hole … when he talked about seeing the color of the cylinder head as being a bad sign is what has me worried because I can definitely see the cylinder head bare metal.
     
  6. nate358

    nate358 Junior Member

    Joined:
    Feb 25, 2012
    94
    19
    0
    Location:
    Columbus, OH
    Vehicle:
    2006 Prius
    Model:
    N/A
    Ok I got a better scope here are photos and video of cylinder 1.

    20220331132850159.jpeg

    Posted via the PriusChat mobile app.
     
  7. nate358

    nate358 Junior Member

    Joined:
    Feb 25, 2012
    94
    19
    0
    Location:
    Columbus, OH
    Vehicle:
    2006 Prius
    Model:
    N/A
  8. nate358

    nate358 Junior Member

    Joined:
    Feb 25, 2012
    94
    19
    0
    Location:
    Columbus, OH
    Vehicle:
    2006 Prius
    Model:
    N/A
    Taken with a Depstech WF028 from Amazon. Considering it was half the price of what Autozone and Napa sell... The quality of the image speaks for itself.

    Posted via the PriusChat mobile app.
     
  9. rjparker

    rjparker Tu Humilde Sirviente

    Joined:
    Jun 6, 2008
    7,918
    4,680
    7
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    I would consider taking care of the oil leaks and don't worry too much about the cylinders right now. You probably don't have a head gasket leak but these engines are bad about that later on. There is not much you can do about oil burning other than a rebuild but you really don't know how much you are leaking versus burning.

    A rebuild with the improved pistons and rings is the guaranteed fix for oil burning but it is an engine out and expensive procedure. However removing the timing chain cover alone, if needed, is not minor. Some report the tensioner was their leak but the timing chain gasket is more common. Most would leave well enough alone unless it starts burning a quart every 1200 miles, which was Toyota's threshold for a warranty repair on these engines when still in powertrain warranty.

    You will find a lot of advice about cleaning out the intake, egr cooler, tubes and valve. It is a good maintenance approach especially before it starts cold start rattling with a head gasket leak. Change your oil every 5k like your wallet depends on it.

    Creating a repair fund and finding a good independent hybrid shop makes the best sense if you plan to keep this car for 50k or more miles. If the head gasket does not get you in the next 50k, the brake booster and hybrid battery are sure to tap the fund.
     
    #9 rjparker, Mar 31, 2022
    Last edited: Mar 31, 2022
    nate358 likes this.
  10. nate358

    nate358 Junior Member

    Joined:
    Feb 25, 2012
    94
    19
    0
    Location:
    Columbus, OH
    Vehicle:
    2006 Prius
    Model:
    N/A
    I'm almost certain it's a head gasket now. I got an adapter in to do a coolant system pressure test. I pumped it up to 15 psi. The #2 and #3 cylinders were all the way up... So I turned the harmonic balancer clockwise to make the pistons even. The #3 looks like oil is coming down the cylinder wall. Here is the video from the borescope:



    Posted via the PriusChat mobile app.