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

2016 Possibly blown head gasket

Discussion in 'Gen 4 Prius Main Forum' started by Josh H, Aug 31, 2022.

  1. Josh H

    Josh H New Member

    Joined:
    Aug 31, 2022
    4
    4
    0
    Location:
    VA
    Vehicle:
    2016 Prius
    Model:
    Four Touring
    My 2016 Prius IV Touring, at 68K miles, starting running rough last week (daily driver for 2+ years and well maintained). I got the Misfire code with a check engine light the next day. I've changed the spark plugs, and noted discoloration on the 1st cylinder (code was for a misfire on first cylinder). I cleared the codes, but they returned the following day. The engine is running more rough, and I noted a lighter color streaked through my oil when I took the cap off to inspect it since I suspected there might be a head gasket problem. I'm not keen on paying to get the gasket replaced, if it will happen again. Anyone have thoughts on what would have caused this?
    20220830_202324[1563].jpg
     
    bisco likes this.
  2. ToyXW

    ToyXW Active Member

    Joined:
    Jan 6, 2018
    153
    148
    0
    Location:
    Sacramento
    Vehicle:
    2010 Prius
    Model:
    ----USA----
    Try swapping the #1 and #2 coils to see if the misfire moves to cylinder #2. Blown head gaskets are rare on gen 4s.

    That picture of the underside of your oil cap does not alarm me - it could easily be normal varnish.
     
    Mendel Leisk likes this.
  3. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,133
    50,049
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    any coolant loss?
     
    Mendel Leisk likes this.
  4. Josh H

    Josh H New Member

    Joined:
    Aug 31, 2022
    4
    4
    0
    Location:
    VA
    Vehicle:
    2016 Prius
    Model:
    Four Touring
    Dealership called and said it was the distributor coil for the first cylinder. I sent it to the shop so as to minimize having the warranty voided. I will remember to try the swapping suggested if this happens in the future. The shop recommended cleaning carbon out of various parts as that was likely the source of the coil going bad.

    Thanks for the tip about the oil appearance not being as alarming as I thought it was. Hopefully it is just that varnish suggested. The oil itself did appear normal to the technicians (I asked for an oil change while it was in the shop already).
     
    jerrymildred likes this.
  5. dacoobob

    dacoobob Member

    Joined:
    Dec 29, 2021
    83
    45
    0
    Location:
    Kansas City, MO
    Vehicle:
    2016 Prius
    Model:
    Four Touring
    this does not say "head gasket" to me, especially on a 2016. more likely an ignition system problem-- i'd replace your coils and wires too and see if that resolves it before looking at the HG.
     
    2020XLEAWD likes this.
  6. Mendel Leisk

    Mendel Leisk EGR Fanatic

    Joined:
    Oct 17, 2010
    56,671
    39,222
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Do you know the code? They can point to specific cylinder(s). If so try post #2 suggestion, swapping coils/plugs between cylinders.
     
  7. CooCooCaChoo

    CooCooCaChoo Senior Member

    Joined:
    Jan 7, 2015
    930
    522
    0
    Location:
    Cow-lee-fornia
    Vehicle:
    2023 Prius
    Model:
    LE
    You shouldn't be able to see oil when you take the oil cap off. If you do see oil, there is too much oil in the car because everything is supposed to drain into the pan. There should be nothing under the valve cover where the cap is. What you are probably seeing is varnish which can be various colors, mostly dark though.
     
    FuelMiser likes this.
  8. jerrymildred

    jerrymildred Senior Member

    Joined:
    Oct 28, 2016
    11,518
    14,128
    0
    Location:
    Tampa, FL
    Vehicle:
    2017 Prius
    Model:
    Two
    That looks like varnish to me and the light streaks, I would guess, are from the end of the funnel scraping it off. Another symptom of a HG failure on a Prius is usually white smoke from the tailpipe. The HG usually fails between the water jacket and the combustion chamber.

    I also think it would be smart to try swapping around the ignition coils to see if the code moves with the coils.
     
  9. douglasjre

    douglasjre Senior Member

    Joined:
    Sep 13, 2008
    1,992
    676
    0
    Location:
    Null, NL
    Vehicle:
    2010 Prius
    Model:
    ----USA----
    How much oil would have to be in the engine to see it poling under the valve cover
     
    jerrymildred likes this.
  10. CooCooCaChoo

    CooCooCaChoo Senior Member

    Joined:
    Jan 7, 2015
    930
    522
    0
    Location:
    Cow-lee-fornia
    Vehicle:
    2023 Prius
    Model:
    LE
    A lot. I've heard/read mechanic horror stories where owners just kept adding oil instead of doing oil changes.
     
  11. douglasjre

    douglasjre Senior Member

    Joined:
    Sep 13, 2008
    1,992
    676
    0
    Location:
    Null, NL
    Vehicle:
    2010 Prius
    Model:
    ----USA----
    Some call these sales opportunities
     
  12. N khan

    N khan New Member

    Joined:
    Jun 22, 2023
    3
    0
    0
    Location:
    London
    Vehicle:
    2017 Prius
    Model:
    N/A
    Hi
    I opened my water pump after many coolant loses and water pump looked orange whT does this mean
    When water pump is orangeish ?
     
  13. Doug McC

    Doug McC Senior Member

    Joined:
    Feb 15, 2022
    1,014
    382
    0
    Location:
    Midwest
    Vehicle:
    2022 Prius
    Model:
    XLE
    That means your whole cooling system is rusting due to depletion of the additives because the coolant wasn’t changed when it actually needed to be. My bet is your inverter coolant is in the same condition. From what I see there, you are going to be spending A LOT OF MONEY real fast.

    That is why Toyota says to check the actual condition of the coolants every 6 months.
     
  14. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,133
    50,049
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    Good news
     
  15. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,133
    50,049
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    How many miles on her? Have you followed the maintenance schedule?