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Should I replace the engine?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by prius@noob, Apr 6, 2022.

  1. prius@noob

    prius@noob Junior Member

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    - Had the same issues initially as The Critic (2011 Prius Head Gasket Failure | PriusChat), cylinder misfires on my gen 3 prius @ 205k miles with knocking and vibration.

    - Replaced the ignition coils with cheap ones from amazon. Check engine light came back on.

    - Replaced the ignition coils with Duralast ones. Check engine light still came back on

    - Replaced the spark plugs. Check engine light came back on. Noticed temp light turning on.

    - Took it to a mechanic for an cosmetic issue, he diagnosed the issue as Engine Coolant Temperature Sensor 1 Circuit Low (code P0117). Also recommended seafoam to be added to fuel to remove carbon build up?

    - Replaced sensor (found the sensor location in this post: [Solved] Engine Coolant Temperature Sensor location? | PriusChat). Everything seemed to work just fine for 2 days. Check engine light came back on and so did the temp light.

    - Noticed Coolant levels were dangerously low, foolishly purchased a Autozone branded one (because i'm cheap too :D). Coolant levels dropped rather quickly same night, topped off and yet they dropped off rather quickly.

    Now, I'm wondering if I should simply the engine coolant and replace with zerex asian cars red coolant. Should I replace the inverter coolant too? Do they mix? Or take it to firestone/jiffylube/mechanic for a coolant + radiator flush (This was recommended by O'Reilly tech (they don't provide flushing services though)?

    At this point I'm $300-400 down and would like to fix it myself (simple stuff only. in case you haven't noticed, this is the 1st time I opened the hood of a car :D). Or should I simply go for an engine replacement (Head gasket issue sounds like too much work for me and I'm still not sure what the root cause might be) ?
     
  2. JC91006

    JC91006 Senior Member

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    where is your dangerously coolant going/ending up?
     
  3. tankyuong

    tankyuong Senior Member

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    Replace engine
     
  4. Mendel Leisk

    Mendel Leisk Senior Member

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    How many miles?

    Ever cleaned the Exhaust Gas Recirculation components, and intake manifold?
     
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  5. prius@noob

    prius@noob Junior Member

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    I tried locating the source, but couldn't find one. I did find wet spot on the ground right beneath the engine coolant box, when refilling with coolant the second time.

    207k miles (Brought at 190k). Never cleaned the EGR components or intake manifold. Will look into it, see if I can perform them myself, if not I'll ask my mechanic if he can.

    Update since posting the question: The mechanic is recommending Induction cleaning? To clear up the carbon build up near the pistons... Is that worth pursuing? He did recommend seafoam which I tried and the car ran much better for a while, alas, that didn't last.
     
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  6. prius@noob

    prius@noob Junior Member

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    @Mendel Leisk - Just clicked on your link and EGR and Oil can and realized both you and my mech might be talking about the same thing.

    In case there were any doubts about my expertise under the hood, please refer to my username :D
     
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  7. 2010moneypit?

    2010moneypit? Active Member

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    Replace engine.
     
  8. Dagoba

    Dagoba New Member

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    I'm new around here but not new to vehicles or wrenching. If your coolant is going somewhere and you have shaking on startup symptoms with a cyl 3 misfire, I don't understand why you'd be caring about which coolant you use or anything about the inverter? Replacing coolant will only give it more chances to hydrolock the cylinder and kaput the while engine via a bent rod or leg out of bed (when the rod goes through the block).

    Listen to those more experienced than I, but in terms of troubleshooting you seem to be just throwing parts hoping something works. Since you're inexperienced with engines it's a good idea to take it to either an independent shop who knows hybrids, or maybe even the dealer. Shotgunning parts will become expensive fast...
     
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  9. johnHRP

    johnHRP Active Member

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    Get 2015-newer engine. Either from local Prius, PriusV, corolla/Auris hybrid from Japan or Europe.
     
  10. prius@noob

    prius@noob Junior Member

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    Sorry in advance if my reply seems defensive:

    I don't really care about the coolant, just read on the forum that OEM or Zerex asian cars one is recommended.

    Right now the car is just sitting there in the parking lot while I wait for a mechanic to be available. Only topped up the coolant since it was pretty low the other day (stopped doing that after noticing leaks :) ).

    As for throwing parts at it, replaced the coils and spark plugs as that was the code I got (P030x). Same with the coolant sensor (P0117, diagnosed by mechanic while getting work done on unrelated issue).

    Honestly, hoping for the best (EGR cleaning) and preparing for the worst (engine replacement).


    How would one go about finding these parts (except calling junkyards and searching on ebay)? Labor cost for replacement also seems to be pretty high unless I can find an experienced user in MO willing to work together on the car like @Rebound or @Raytheeagle. :D
     
  11. johnHRP

    johnHRP Active Member

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    It depends on the market value of the car. You can check from VIN number, which cars the engines are from.
     
  12. rjparker

    rjparker Tu Humilde Sirviente

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  13. johnHRP

    johnHRP Active Member

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    It depends how bad the short block is, we can replace the piston and piston rings but the piston wall is practically cannot be refurbished.
     
  14. prius@noob

    prius@noob Junior Member

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    I'm sure I'm grasping at straws here, but does anyone know what this white cap is right next to the engine coolant temperature sensor is? It's missing on my prius. (Pic provided by @Mendel Leisk in another thread)
     

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  15. Mendel Leisk

    Mendel Leisk Senior Member

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    Yeah I think mechanics will lead you to coil/plug replacement first, basically 'cus it's a walk-in-the-park for them. If you have a misfire on a particular cylinder, simply swap coil and plug from that cylinder with another, and see if the code changes. If not, it's likely head gasket failing.

    With 200K plus and no EGR cleaning done*, I'd be thinking head gasket failure, test and address that first. Leak-down test and/or boroscope inspection of the cylinders is best for that.

    Don't neglect the EGR, but if the head gasket is already failing, starting with EGR cleaning will be "closing the barn door after the horses have bolted".

    * My 2 cents: EGR cleaning should be done at the least, at the same interval as engine coolant change: 100K miles or 10 years, then 50K miles or 5 years thereafter. And yeah, Toyota doesn't want to know about it; issue bulletins on the subject, saying wait for the shakes, or codes, and that "the majority of vehicles will not experience this". Which is BS.
     
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  16. Mendel Leisk

    Mendel Leisk Senior Member

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    Trust me I'm in the same boat. I've done the EGR and intake cleaning, but it was a hurdle for me. It's not that hard, once you get into it. Just for an overture: try taking off the bottom bracket nut on the EGR cooler. This can be done without removal of anything else, it needs to come off eventually, and it can be left off. That nut is just a royal pain to get to, best dealt with first. It's 12 mm socket IIRC, and you will want to have an assortment of wrenches (swivel head helps), extensions, reg and deep sockets. It takes something like a reg socket and 3" extension, or a deep socket and 1.5" extension. And some pulling cables/brackets out of the way temporarily. The nut in question is just on the far side of a large coolant hose going into the engine, around 3 o'clock (relative to that hose), as you face the engine bay from the driver's side.
     
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  17. prius@noob

    prius@noob Junior Member

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    In the process of following this video 1st to check for build up in EGR pipe. Looks simple enough for me. If I find some build up, there's some hope (i think?), and will proceed to other build up cleaning. If not I'll have the mech do the induction cleaning. He mentioned he has a machine for that and it's the likely cause for engine knocking/rattling.

    I'll ask about the leak down and boroscope tests. Hopefully they don't cost too much.
     
  18. prius@noob

    prius@noob Junior Member

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    Update: Got around to removing the EGR pipe and cleaned it a bit. Is this amount of carbon build up normal?

    I need get off my butt and clean the intake and close it up. :D
     

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  19. Paladain55

    Paladain55 Active Member

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    Cylinder misfires and losing coolant? Better replace the head gasket and head bolts while you're in there. That motor is about to be done if you keep driving it. Honestly I would just pay someone to change the head gasket. I think the Gasket Masters quoted $1500-$2000 depending on if they did it mobile or at their shop. You could find something like that locally with a jdm mechanic.
     
  20. Mendel Leisk

    Mendel Leisk Senior Member

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    A little hard to judge (due to your camera's auto-exposure, but I'd think, partially due to the pipe's appearance:

    upload_2022-4-8_13-28-50.png

    And more so the miles, that the cooler/valve and intake manifold are overdue for cleaning. But, I would consider leak-down and boroscope checks of the head gasket first; the EGR cleaning boat has sailed.

    But yeah, EGR and intake cleaning needs doing.