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Engine knocking, CEL, fouled plug, and lost coolant

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Sammy B, Jan 29, 2017.

  1. Sammy B

    Sammy B Member

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    Hi y'all,

    My 2010 Prius currently has about 180k miles on it. I bought the car new, and have religiously done all my own maintenance on the car. Since it had about 70k miles on it, the engine started burning oil. It progressively has been getting worse and worse up until about two months ago where it was burning about a quart every 400 miles. [Yes, I tried getting it repaired under warranty, but Toyota refused to acknowledge there was a problem.]

    A couple months ago, the engine started to shake violently. Usually this was during startup, but sometimes it would happen when the engine was hot during acceleration from a stop. Shortly after this started happening, it threw a code P0302 (misfire in the number 2 cylinder). After checking the plugs, I saw that the #2 plug was pretty badly fouled with oil. The other three were normal. To make matters worse, I also started loosing coolant somewhere. There are no apparent external coolant leaks, however the oil looks completely normal, and oddly enough, I am not burning as much oil as I was in the past.

    Any thoughts on what the problem might be? I saw the bulletin for the intake manifold, but I'm not convinced that this is what the problem is -- although it may contribute. I've heard everything from the EGR, intake manifold, cracked block, etc. I'm thinking it's a head gasket, but a second or third opinion would be much appreciated.

    Thank you in advance,
    Sammy
     
  2. tankyuong

    tankyuong Senior Member

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    Headgasket,you will notice a lot of vibration when traction battery goes down to two bars
     
  3. Raytheeagle

    Raytheeagle Senior Member

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    How much coolant is it using? What is your oil consumption now? Did you switch viscosities of oil? Have you checked below the throttle body? Have you pulled the intake manifold before? Was there any carbon buildup?

    Keep us posted(y).
     
  4. saltdiscus

    saltdiscus Member

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    Did you just went to one dealer only.Why don't you goto different dealer as well as certified hybrid mechanics and have a look with them then call your insurance .

    Posted via the PriusChat mobile app.
     
  5. Sammy B

    Sammy B Member

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    I haven't pulled the intake yet, but I might try that before taking on the head gasket. It's loosing about a quart of coolant every few hundred miles, and about a quart of oil every 800 or 900 miles. I've always run 0W20 synthetic.

    I don't think I've ever taken the car to to dealer for any kind of service except for complimentary oil changes.
     
  6. Raytheeagle

    Raytheeagle Senior Member

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    The only code you are getting is for misfire in cylinder #2? The violent shaking under load to me suggests a restriction in the air flow side. Or a fuel pump issue. IMO it is worth pulling the intake manifold and egr pipe. Might also pull the egr valve attempt to actuate it. Ever do the throttle body or MAF sensor cleaning? When cleaning the intake manifold, ensure the passages from the egr are cleaned and do a compressed air flow test to ensure all passages are free flowing.

    Still may have a head gasket issue, but worth investigating as this will not take that long(I did the intake, throttle body and MAF in 2 hours) and potentially provide some insight ;).

    Hope this helps(y).
     
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  7. bisco

    bisco cookie crumbler

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    amazing how many high mileage 2010's we've been seeing lately.
     
  8. Sammy B

    Sammy B Member

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    Thank you, Ray! I will tear it down this weekend. I'm pretty sure that I'll still have to do the head gasket, but it sounds like the intake and EGR are something that should be done anyways.

    Yeah, I put a hell of a lot of miles on this car. Way too much commuting!
     
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  9. Raytheeagle

    Raytheeagle Senior Member

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    I am at 147 k miles on our 2010 Prius II. Commuting is what I do too:(.

    I did the intake and complete egr system which included replacing the egr cooler at 120 k miles. Happy I did so ;).

    If you have not done the intake or egr pipe yet to know the condition, my suspicion is that it will be clogged with deposits and may explain some of the shaking behavior as the engine will be slightly starved for air.

    As for oil consumption, why not try going up in viscosity, say to 5W-30? Being in So Cal, the increase in viscosity you would not see and may help decrease your priuses drinking problem. I run full synthetic 5W-30 and it has helped(y).

    Keep us posted(y)
     
  10. Mendel Leisk

    Mendel Leisk Senior Member

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    Doesn't sound good. (n)
     
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  11. m.wynn

    m.wynn Senior Member

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    Good lord, the blown head gaskets just won't stop. Sammy B, please check your water pump for seized impeller. It would be awesome if we could start getting an idea of WHY this is becoming such a Gen 3 thing.



    I'm thinking all the recent threads of folks chasing dead-end misfires would be solved if they were all looking in the cylinders with borescopes. Time for a recall on this engine. Head gaskets, water pumps, pistons and control rings and a re-designed EGR/intake manifold system for all. Is that too much to ask? These engines are NOT up to Toyota standards. Even the planned obsolescence theory doesn't fly here. These things are dropping dead at under 7 years old and under 200k miles.
     
    #11 m.wynn, Jan 29, 2017
    Last edited: Jan 29, 2017
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  12. JC91006

    JC91006 Senior Member

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    200k miles is just about where Toyota expects you to upgrade to another Toyota
     
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  13. m.wynn

    m.wynn Senior Member

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    Sure, you could even say 180k - Toyota's own stated vehicle "life expectancy". But who here really expects their 2010 or newer motor dead from head gasket failure at under 200k miles?
     
    #13 m.wynn, Jan 29, 2017
    Last edited: Jan 29, 2017
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  14. Sammy B

    Sammy B Member

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    Oh yeah, the reason why I discovered that the coolant was low is because the coolant temp dummy light came on and the heater stopped working. Adding more coolant was a band-aide solution to both issues.

    I'm going to have another driver in the family within a couple years, so I'll need to get a little more life out of this Prius! 200k mile life expectancy just won't cut it. And, if I do need another car, it won't be a Toyota this time around, which is too bad. Except for the oil consumption and recent drama, the car has been flawless.
     
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  15. JC91006

    JC91006 Senior Member

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    Was the coolant ever changed on the 2010 with gasket failure?
     
  16. Raytheeagle

    Raytheeagle Senior Member

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    If the light told you of the issue and you were adding oil every 400 miles, would you have looked at the coolant reservoir when adding oil to keep an eye on the level? Or were you only watching the dipstick for the oil and not concerned with anything else when under the hood? Reason I ask is with that warning light and the frequency of your oil additions, if you were looking at the coolant reservoir and other things while adding oil, that is a bad sign. Have you been adding coolant ever since the light came on? If so how much and at what frequency?

    Used engines can be had from salvage yards from lower mileage rear end damaged Gen 3 Pri, so I would start looking for one and find a decent mechanic who could do the swap. This is if the other components in the car are all in good working order.
     
  17. Rebound

    Rebound Senior Member

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    Seems like we're ignoring the fouled spark plug. Why is it fouled? Bad rings? Bad ignition? Bad gasket?
     
  18. Samprocat

    Samprocat Active Member

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    Now don't just take after all you read on internet.....a lot of people are not telling the truth and especially how many people only know how to drive and care less what happens under the hood.....
    There is many people that keep car for 36 months and don't spend any money on maintenance beside time to return to dealership.....so many used car's on market are one oil change before trade in.....
    If there is issues with this problems so high .....Why none of people that do maintenance in recognized shops or Toyota services never complain.....
    There is big percentage of neglect with so many people that complain about problems.....
    I do services on Taxi Toyota Prius almost daily .....and some of them are in 300-400 000 miles radius and with maintenance on schedule still run good....
     
  19. Sammy B

    Sammy B Member

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    I would usually check the other fluid levels when changing the oil. I changed the coolant about 50k miles ago -- no obvious gasket problems, just a normal coolant change.

    I'm loosing about a quart of coolant every few hundred miles, so it's something that became pretty bad over a short period of time. If I'm not mistaken, a bad head gasket would account for the misfire, fouled plug, and coolant lose.
     
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  20. Mendel Leisk

    Mendel Leisk Senior Member

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    Yeah that's the smoking gun. :(

    Just editorial: the word you want is "losing", not "loosing".