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Prius 2013 engine bay gets real hot when a/c turned on.

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by AliPK, Sep 19, 2018.

  1. AliPK

    AliPK Member

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    Hi guys. Just noticed that engine bay including the fenders and head lights were pretty hot to touch after driving only a few Km with a/c turned on.had to pop the hood to get it cooled down.is this normal or I should be worried??? It's 2013 prius jdm with 76k km.
     
  2. bisco

    bisco cookie crumbler

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    tough to diagnose heat over the internet
     
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  3. AliPK

    AliPK Member

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    Any usual culprits?
     
  4. bisco

    bisco cookie crumbler

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    i don't think i have ever heard of it before. i suspect that if it is hot out, and you are in the sun, the engine bay would get pretty warm.
    but how to determine if it is abnormally warm? perhaps a differential infrared temp measurement with the a/c off and on?
     
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  5. sam spade 2

    sam spade 2 Senior Member

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    IF.....the radiator fan is running whenever the A/C is actually pumping out cold air, then it's probably normal.

    Unless a previous owner screwed with something like grill shutters........or your radiator has picked up a WalMart plastic bag or two.
     
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  6. AliPK

    AliPK Member

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    Car is parked in shaded garage, dropped the kids at school (16 km round trip) and it's kinda burning hot.just Wana know if this is the normal behavior.
     
  7. AliPK

    AliPK Member

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    So if I see my radiator fan running then I shouldn't be worried?
     
  8. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Fans should be running. Remember: air conditioners don't make cold. They move heat.

    Car air conditioners move heat from the cabin air to the air coming through the front grille. The fan is necessary to pull more air through, especially when you are at a standstill.

    The air travels backwards from the condenser (where the cabin heat is dumped) then through the radiator, then into the engine compartment. From there it naturally breezes out. But while it is in there it will heat up everything it passes- the hood, the fenders, the headlamps, undercarriage etc.
     
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  9. AliPK

    AliPK Member

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    Thanks now that makes sense
     
  10. Jimi1976

    Jimi1976 Active Member

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    Do you get an overheating CEL?
    If not....well, engines get hot
     
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  11. FuelMiser

    FuelMiser Senior Member

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    I would make sure I had genuine Toyota-brand pink coolant in both the engine and inverter reservoirs.
     
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