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How to determine if the water pump needs replacement?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by NoviceMechanic, May 14, 2020.

  1. NoviceMechanic

    NoviceMechanic New Member

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    I have a 2010 PRIUS T SPIRIT VVT-I CVT 3rd Generation. A few months ago I had a problem with cabin heating followed by indication of engine warming. When I got the car serviced at an authorized Toyota service centre they told me that there was a coolant leakage and they fixed it by loose pipe fitting. However, they also told me that the water pump needs replacement to resolve the engine heating issue.
    I didn't get the water pump replaced though. The coolant leakage has now stopped, however, I still get the engine heating symbol sporadically when I take a car for long drive.

    How can I determine if the water pump indeed needs changing as it is quite expensive to replace it?
     
  2. pjksr02

    pjksr02 Active Member

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    How many miles are on your car? Can you hear your pump running (from outside your car) when you turn on your heater-like a buzzing sound?

    If you can DIY, the job is easy, and the pump is around $235 from a dealer. The pump simply bolts onto the side of the engine. At ten years, if you plan to keep the car, a new pump is cheap insurance. Many owners have had pump failures.
     
  3. Peter123

    Peter123 Active Member

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    The original equipment manufacturer is Aisin. Their part number is WPT190. There is a separate water pump for the power inverter, Aisin WQT001, and it is cheaper. You should be able to find something for £150 to £200. I do not know what a dealer charges for it in the UK.
     
  4. Mendel Leisk

    Mendel Leisk Senior Member

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    I'd second this. I think runtime is what brings them to failure. What's the concensus, somewhere between 125~150K miles it should be replaced?

    Maybe a lot more in UK, just judging from past postings here. The Aisin pump below might be best bet for buyers outside the States:

    Genuine Toyota 161A0-39015 (161A039015) PUMP ASSY, ENGINE WATER - Amayama

    (View the photos with the Aisin pump, the box lists compatible vehicles/engines.)

    Or even in the States? Worth noting:

    1. Throw in a few extras (say wiper blades, air filters) and the shipping cost often doesn't budge, or just a small amount extra.
    2. Try to keep purchase from one country (either UAE or Japan) will ensure only one shipping charge.
    3. In my experience with small purchases, around $100 CDN max, there was no sales tax or duty.
     
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  5. NoviceMechanic

    NoviceMechanic New Member

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    I think I will take your advice and replace the pump anyways. Thank you.
     
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  6. Mendel Leisk

    Mendel Leisk Senior Member

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    @NoviceMechanic, just to clarify, since part of your response got encapsulated in the quote: your car has 91K miles, and you hear a whizzing sound when turning the car on.
     
  7. NoviceMechanic

    NoviceMechanic New Member

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    Yes, that is right.
     
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  8. Mendel Leisk

    Mendel Leisk Senior Member

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  9. Raytheeagle

    Raytheeagle Senior Member

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    Is there a way to read the trouble codes:whistle:?

    Since the engine water pump is magnetically driven, troubleshooting it is tough:cool:.

    But I've done the replacement job 3 times and each time found the impeller to be restricted and in one case, rubbing against the internal housing:eek:.

    @The Critic had his water pump fail early on in his Gen3's life (around 130k IIRC), so it happens ;).

    Hope that helps(y).
     
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  10. Paul E. Highway

    Paul E. Highway Active Member

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    I replaced my 2010’s water pump at 156,888 miles as cheap insurance.
     
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