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Weird pumping noise coming out of 2009 gen 2?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Jakov Glavina, Nov 16, 2024 at 2:37 PM.

  1. Jakov Glavina

    Jakov Glavina Junior Member

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    Hello!

    I have a 2009 gen 2 prius, regularly maintained and without any problems, which was in pristine condition until a few weeks ago when I had a traffic accident. I had a replace a handful of things, most notably the AC radiator and water radiator, radiator fan shroud assembly, and front cowling. Also a few body parts (hood, front bumper and fenders).

    I managed to get all parts replaced (most of them being OEM either new or from used cards), with less important parts (e.g. headlights) being aftermarket. I make sure that the most important ones (electrics, cooling) etc. were OEM.

    Now, I'm at the point where I need to bleed the coolant/air from the cooling system after having replaced the coolant. However, upon doing so, I noticed a weird noise coming out from near the inverter portion of the vehicle.

    Here is a video demonstrating the noise: https://youtube.com/shorts/TkRXKX1Y3vc

    Do you have a clue on what the noise might be? I should note that the part replacements were not performed by a Toyota dealership, but a body shop, so I'm suspecting it might be that they have perhaps hooked up a part of the piping or something else in the wrong manner. Do you think this is a faulty part or just an incorrectly hooked up system? I'm leaning against the latter since after the accident I turned on the car for a short while and during that time this weird sound was not present, only after the work was performed by the body shop did it start occurring. I'm hoping its an easy fix, though. Thanks!
     
  2. Hayslayer

    Hayslayer New Member

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    Coolant control valve cycling? Maybe hoses are connected wrong?
    If you look behind the driver headlight, you'll see the inverter pump.
    To the left of that pump and mounted slightly lower is the coolant control valve. Is that where the noise is coming from? Maybe you can unplug it and see if the noise goes away.
     
  3. Tombukt2

    Tombukt2 Senior Member

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    There nothing spinning around down there so if the engine's not running and the fans aren't on or even if they are on carefully you can just reach down and put your hand on the coolant control valve is that what's making the honking you'll feel it in your hand don't snatch it away it's not going to hurt you Just let your hands sit there and feel the honking now you know it's the coolant control valve The hoses should all look like they belong where they are they're preformed pre-bent if somebody puts them on incorrectly hoses will have extreme angles on them and look fubar. So if someone can send you a picture of the coolant control valve connected properly and a clear picture you should be able to look at that picture and look in your car and tell if somebody has screwed up the hose connections which is possible they're all the same size so some American car mechanic could just twist something and stick it right on there thinking it's good to go this valve has awful lot of ports on it I wonder yeah that sort of thing It happens. There's also a coolant heat storage tank right under your inverter pump under the fender wall behind the fender liner that pump can get to making funny noises too especially if you're coolant isn't bled properly etc this is a hard car to get full of coolant have heat and all that properly it can't be done really quickly It's kind of a pain.
     
  4. Jakov Glavina

    Jakov Glavina Junior Member

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    Hello everyone, thanks for the replies!

    For anyone that might find themselves in a similar situation, we identified the problem and fixed the issue. The problem was in the hose that goes from the inverter coolant reservoir to the inverter pump - that specific hose was absolutely full of air, so much so that the coolant wasn't able to go through. I suspect that when the coolant was being replaced/refilled, it might have been done too hastily, resulting in large air pockets ending up trapped in the piping. To solve this, we literally "massaged" the hose to push out the air by hand in the direction of the coolant reservoir. That was confirmed since a handful of bubbles immediately started coming up in the reservoir. Once the air escaped, the sound vanished. Hope this helps!
     
  5. Tombukt2

    Tombukt2 Senior Member

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    Yes this is milking the hose You squeeze the hose like you do a cow's utter for milk . You hear this talked about on this site all of the time usually when you're filling the reservoir this will get pumped out very quickly I don't know how you guys managed to make this happen but good on you that you found it and you figured out squeezing the hose and then topping off the reservoir and watching the water ripple and all of that stuff I think it's all here in the text but there's 40 different threads about the inverter pump hell maybe a hundred I'm sure no one has time to read them all but this is very common I am glad y'all came to this conclusion very good.