Overheating again

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by johnnychimpo, Jun 25, 2021.

  1. johnnychimpo

    johnnychimpo Member

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    Someone refresh my memory on the following
    1.fuses for water pump and how to test it all i got is a test light
    2.cooling fans and what is normal function

    the story my EGR got stuck open I will need to replace it. unplugged it moved on
    it got really hot as the EGR cooler cant deal with it stuck in open state sucking in hot exhaust all the time.
    now closed and disconnected. car pulled a code saying engine wont start so I unplugged the main white wire in the fuse box to clear the code memory. engine start runs fine it complained about the EGR but its disconnected so I can ignore that. No other codes to display. test drove it but noticed the coolant getting to 210 F.
    not normal. coolant level is normal and radiator fans are spinning so is my pump bad or fuses burned out. or the fans not working optimally. Sorry guys it is late I hope Im making sense.
     
  2. johnnychimpo

    johnnychimpo Member

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    Slight update, I connected an spare pump that I have and it spins up so power is not a issue. coolant is still at normal levels so I think either impeller maybe maybe could me worn or thermostat is stuck or bad (how do I test if it is stuck closed.) Else fans are the last thing I can think of that is not working as they should as they do spin but not sure how fast the should be going.
     
  3. Mendel Leisk

    Mendel Leisk Sand Pounder

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    You replaced the head gasket in February? Had you had the car long? Maybe previous owner tried stop-leak coolant product?
     
  4. ChapmanF

    ChapmanF Senior Member

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    Pot of water on the stove, easy test.
     
  5. Mendel Leisk

    Mendel Leisk Sand Pounder

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    When I did that it was after purchasing replacement thermostat. I suspended them both in the pot, brought the temp up and you could really see the difference. First off, the old one's gasket was hardened, and the edges frayed/chipped. Then, as the temp of water climbed, the old one opened sooner.

    My issue was excessive cooling when driving on a cool morning on a "weekend" freeway, not many other cars on the road.
     
  6. mjoo

    mjoo Senior Member

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    Johnny has a gen4 engine in a gen3.

    How many miles on the gen4 engine?

    moto g power ?
     
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  7. johnnychimpo

    johnnychimpo Member

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    Thanks but it seemed to have resolved itself. My theory here is the EGR got stuck open and it got supper hot after all it is exhaust gas going in all the time and I don't think the EGR cooler is meant to be able to cool it when it is stuck open. In any case I think it got so hot it created steam/air bubble causing flow issue once it cooled overnight it went back to liquid . this morning drove it for 40 min it got to 212 once then never went above 208 now it goes between 196 to 204 tops. let me know what you guys think. I have a long trip to Vegas hopefully i am correct here and this is a non issue.
     
  8. johnnychimpo

    johnnychimpo Member

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    this engine I got with supposedly 10 K miles from a totalled JDM supplier I suspect true as one of the valve cover bolts looked slightly bent, I suspect from an accident.
     
  9. mjoo

    mjoo Senior Member

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    Is there a VIN on the engine that you can look up?

    moto g power ?
     
  10. Mendel Leisk

    Mendel Leisk Sand Pounder

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    Yeah this. Something problematic with the coolant hose rework?
     
  11. johnnychimpo

    johnnychimpo Member

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    no its a JDM so VIN.
     
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