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2014-15 head gasket problems?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Lincoln P, Apr 3, 2023.

  1. Tombukt2

    Tombukt2 Senior Member

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    I have an early red 2010 solar roof JBL stereo leather interior five-door Prius that I bought I want to say with $180,000 mi on it almost side unseen at a car lot for my wife she just wanted it because it was red and it got good gas mileage The original owner of this car put all the miles on it mostly highway miles and had done nothing to the car except oil changes and a couple of campaigns at the dealer I don't really know what they were and I don't care something to do with the inverter the chip It was one of them. I bought the car and immediately driving the car home from this little stupid car lot HV battery light issues started to show up on the dash funny how they didn't show up on the test drive and we drove the piss out of the car came back the next day nobody had touched the car and the 12 volt was dead I jumped it with my noco the guy knocked $500 off the car this is right before the pandemic I took the deal anyway drove off with the car body was perfect got the lights for the HV battery in route to my house with the new purchase 09 following behind us. Bring the car to my house open up the area for the HV battery frosted nuts black bus bars you name it standard water leak in the trunk is visible clean all that up fix it I call my friend at a junkyard got a junkyard HV battery that we've put $105,000 mi on and the car is now sitting at right at 300k with 10K oil changes no EGR cleaning that I know of that we've done and the car's been in the wind every day since we left the car lot with it and that I believe is why the car is running as perfect as it does this car does not skip a beat at all. Just this week the brake lights have started coming on intermittently they'll go back off but they starting to stay on more than not brake pedal works perfectly.
     
  2. MikeDee

    MikeDee Senior Member

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    Here is a short video from Gasket Masters. They say they are repairing a LOT of blown head gaskets in Gen 4's. I guess Gen 4's are now getting enough miles for this problem to be evident. Gen 4's have an EGR system that doesn't clog. Kinda blows away the theory that clogged EGR systems cause head gasket failures, doesn't it? That means the temperature cycling theory is the probable cause. Unfortunately, unless you change your driving habits and avoid stop and go/city driving, you can't do much about it other than maintaining your cooling system to prevent overheating. Fourth generation Prius head gaskets are starting fail.  - YouTube
     
  3. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Interesting. I'm sceptical though; wouldn't "blow away that theory" too soon.

    Priuschat has pretty much zero fourth gen head gasket failures reported. Could the 4th gen head gasket failures GM''s encountering be related to coolant loss at the exhaust heat recovery system?

    It'd be nice if he'd stop moving the head gasket around for a bit, and maybe a close-up of the cylinders, see which one(s) is(are) steam-cleaned. Would also help to know the miles on that one.

    Any Gen 4 Owners Out There With Blown Head Gasket ?? | PriusChat

    Here's another short from GM, where they describe an exhaust heat recover bypass as "best method to avoid head gasket failure on 4th gen":

     
    #43 Mendel Leisk, Apr 11, 2023
    Last edited: Apr 11, 2023
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  4. rjparker

    rjparker Tu Humilde Sirviente

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    Every car has head gasket problems, primarily caused by overheating. Decades ago engines without knock sensors could blow hgs with excessive load and poor octane.

    Gen3s have a more systemic series of design flaws that blow head gaskets without traditional engine overheating. Cylinder wall temperature fluctuations are a key factor in hybrid gen3s combined with massive carbon buildup through oil consumption. Both of which were redesigned in gen4.

    Gen4 Cylinder Wall Insulators
    Prius Gen4 Cylinder Insulator.jpg
     
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  5. GregC1979

    GregC1979 Active Member

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    We've seen several Gen 4's as well for head gaskets. You're "getting warmer" no pun intended as to why. And yes, EGR theory...well, it helps the Gen 3's for other reasons just not this one.
     
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  6. MikeDee

    MikeDee Senior Member

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    How many Gen 4s have enough miles to fail head gaskets? Given people drive on average 12K miles a year, not too many. How many of those people with failed head gaskets even heard of Prius Chat? Relatively few I imagine.

    What vehicle function does that bypass remove (is it advisable to remove that function)?
     
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  7. jdenenberg

    jdenenberg EE Professor

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    The heat recovery system warms the engine up faster. Bypassing the heat exchanger just makes the Gen4 warm up like other cars.

    JeffD
     
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  8. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    4th gen exhaust heat recovery system has been leaking, Toyotas acknowledged it, but replacement components are in short supply. Dealerships are not doing bypass, as it “compromises pollution controls".

    neglecting some sort of remedy can lead to significant coolant loss, which can in turn lead to head gasket failure.

    3rd gens also have exhaust heat recovery, but haven’t had leaks.
     
    #48 Mendel Leisk, Apr 11, 2023
    Last edited: Apr 11, 2023
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  9. GregC1979

    GregC1979 Active Member

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    there have been 2016 Taxi's on the road for now for nearly 8 years...trust me, there's plenty of high mileage Gen 4's out there.
     
  10. Grit

    Grit Senior Member

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    From bill Norton’s camp, we want actual data otherwise it’s all speculations and feelings.
     
  11. GregC1979

    GregC1979 Active Member

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    I mean, I work in the industry and I see them all the time come into the shop...also, if you do the math you won't have to ask that question.
     
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  12. MikeDee

    MikeDee Senior Member

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    So what are you saying, does the Gen 4 have a head gasket problem or not?
     
  13. MikeDee

    MikeDee Senior Member

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  14. Mendel Leisk

    Mendel Leisk EGR Fanatic

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  15. MikeDee

    MikeDee Senior Member

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    Well, I tell you what, reading this subforum would lead one to believe that the Gen 3 Prius with over 100K miles is a very unreliable car, so there is that as well.
     
  16. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Not without cause. And any 3rd gen for sale, with miles around 150K or higher, I'd say odds are better than even it's got a failing head gasket, maybe masked with a head gasket sealant product.
     
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  17. MikeDee

    MikeDee Senior Member

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    I'm not doubting that. However, I'm not getting a good sense that these problem vehicles were being maintained well like with respect to oil and coolant changes, are being repaired with non OEM parts, or maybe were being driven too hard. One would think I should have an oil burning problem on my 2013 with 105K miles, but it doesn't burn any oil.
     
  18. GregC1979

    GregC1979 Active Member

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    I already said that in a previous post, but yes..the early ones 2016-2017 are indeed. I've seen some Uber cars (2019+ facelift Gen 4) with well over 100k as well but no issues yet en masse. Taking care of the car with frequent oil changes and coolant flushes/water pump changes will mitigate it some as Mendel points out. I highly recommend the type of driving where your engine doesn't sway too much in temperature changes too frequently like LONG bouts of stop and go traffic or short trips to the grocery store and back home. Watching my daily routine temperature gauge fluctuations, it takes a LONG time to hit 190 degrees and stay in that operating temp range (like at least 5-6 miles of highway driving at 65mph). The cool down takes 5-10 mins in electric only driving to drop by 10 degrees or so but the fluctuation from nearly cold again to warm several if not hundreds of times per day takes it's toll eventually. (coupled with poor mainenance, long oil change intervals, aggressive/accessive acceleration, etc etc...) these engines were not designed to pound hard like a normal gas engine.

    (Also folks, let your engine hit 104 degrees then shut off before you start moving every...single....time you go somewhere. Tap the gas pedal when you first get in in Ready Mode and get the engine circulating. You'll hear towards the end of that first cycle the RPM/fuel trim change in pitch, you can start moving at that point. Too many of you just bomb down the street on a cold Engine without warming it up to operating temps).

    That list that doesn't show the Gen 3 Prius has lost it's mind, it's almost like Toyota threw some hush money at the editors to avoid implications (not like WE don't already know the Truth) lol.
     
    #58 GregC1979, Apr 13, 2023
    Last edited: Apr 13, 2023
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  19. MikeDee

    MikeDee Senior Member

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    I'm now checking my vehicle often for oil and coolant levels. Wasn't doing that before. Going to switch to 5K intervals on the oil and filter too. Thinking about an early spark plug change, EGR system, clean, and water pump replacement too.


    iPhone ? Pro
     
    #59 MikeDee, Apr 13, 2023
    Last edited: Apr 13, 2023
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  20. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    That stuff is good for sure. But the only mantra I've been pushing is EGR clean by 100K (at the latest), and 50K thereafter. Easy to remember, same interval as engine coolant change. That's just my theory, but a lot of factors seem to corroborate the connection.
     
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