2005 gurgling noise under dash???

Discussion in 'Gen 2 Prius Main Forum' started by ggarman, Nov 9, 2007.

  1. ggarman

    ggarman Junior Member

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    Just bought a used 2005 with 56K on it.

    Every once in a while, while I'm on the road, I will here a water gurgling noise coming from deep under the dash near the floor. I'm pretty sure it isn't the coolant pump pumping into or out of the thermos because I know the sound and this noise happens after I've been on the road for a while.

    At first I thought it might be a plugged A/C drain hole, but the noise can happen while I'm just cruising along, not turning or anything. My next thought is coolant moving through the heater coil, but you shouldn't hear air bubbles like that in the coolant lines, right?

    This is the first weekend after we got it, I'm going to be giving the car a real good inspection and maybe I'll find what it is then.

    Is this a normal noise? It is fairly faint, have to have the radio off and windows up to hear it.

    Thanks,
    Greg
     
  2. Rangerdavid

    Rangerdavid Senior Member

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    Actually, its me. Yup, ok, I'm busted. But it was me, I was under the hood of your Prius... :lol: :lol:

    It may be one of the clogged drain holes under the hood just under where the windshield meets the dash. Check these, I've unplugged one before and prior I had hears sort of a sloshing sound....

    Good luck.
     
  3. drifty1955

    drifty1955 New Member

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    <div class='quotetop'>QUOTE(ggarman @ Nov 9 2007, 10:12 PM) [snapback]537558[/snapback]</div>
    I know exactly what it is. Someone home changed the radiator coolant on the car. My last car a new Nissan Sentra (owned like 4 so far) did the very same thing because I did a bad thing which is tried to dump & replace the coolant. I dumped the radiator and did not take out the thermostat so thought I could get away with it. I knew about the trapped air deal with this car so went carefully but: It really gets air bubbles if you try to replace the thermostat. It seems on this Nissan model any coolant change is a no no because its really really hard to get all the trapped air out. The dealer has a special vacuum device they hook to the rad to evacuate the air. It made a gurgling water leaking sound under the dash for about 3 weeks. Its coolant flowing through the heater coil under the dash with bubbles in it. Solid water flow is silent. I finally left the rad cap off and let it run for a while with the heat on for a while on a Saturday and it finally went away.Not sure how hard it is to change the coolant on our cars but I bet it has the same issue. The dealer can evacuate it, if its driving you nuts. Good luck.
     
  4. galaxee

    galaxee mostly benevolent

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    :blink: unfortunately for you, drifty is probably right.

    never tried it that way but DH supposes if you turned the heat on high, defrost, all that, that the engine might keep running...

    try to keep the engine running for about a half hour, basically. take the radiator cap off. can't guarantee it will work but it's worth a shot before heading to the dealer.
     
  5. Bear68

    Bear68 Member

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    Just to expand on Galaxee's advice, which is quite sound, try rising the front of the car on ramps or jackstands. Be sure to block the rear wheels. Air bubbles in the cooling system will obviously go to the highest point. Racing the engine will help increase the flow of coolant. Use a prop or a helpful foot to keep the pedal to the floor and the ICE will run at pretty much the fastest speed the ECU will allow.
     
  6. kenallwein

    kenallwein New Member

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    If you can hear it behind the dash - then the sound is coming from the lines behind the dash.... The heater lines. As others have mentioned, you have air in your system. Easy steps first - cars are setup to "burp" themselves - this takes place after a heat cycle while the engine is off. Make sure your recovery tank under the hood is about half full of coolant, and the car should take care of the rest (it will need several of the cycles to complete the job). And remember - since some of the air is in the heater lines, you are going to need to run the heater.

    Kenny
     
  7. ggarman

    ggarman Junior Member

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    Thanks for all the input! :)

    I believe you are right about the coolant, I checked the coolant today while inspecting the car and the resivour(sp?) was empty and I took the radiator cap off and it wasn't filled to the rim. Added as much as the radiator could take, squeezing tubes and running the engine for a while to help 'burp' it and filled the resivour to the correct level, I'll keep an eye on the level for a while until it stops sucking it dry. Maybe next weekend tilt it up and run it open, we'll see how things go this week.

    I've changed the coolant out several times over the years and yes if you want to do it right, pull both radiator hoses and thermostat and, if they exist or aren't corroded over, the plugs that are on the side of the engine block. Never had a bubbles issue like this.

    I know the coolant was definitly changed because it is green, I was expecting red. It sort of ticks me off that it was changed cause I was hoping for the original to be in there with its long life and all.

    I haven't done a search yet, but is the original coolant really all that great or is it just hype and one should never wait 100,000 miles before changing the coolant?

    RangerDavid, so that was you under there! I thought I heard something scurry off this morning when I started nosing around. :D

    Thanks,
    Greg
     
  8. galaxee

    galaxee mostly benevolent

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    <div class='quotetop'>QUOTE(ggarman @ Nov 10 2007, 03:05 PM) [snapback]537749[/snapback]</div>
    yikes!!
    get that crap out of your engine ASAP!!!
     
  9. Bear68

    Bear68 Member

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    Oboy! Again I get to agree with Galaxee!! :p

    Factory long life coolant is red with a 30k mile life span. The NEW factory SUPER long life coolant is Pink and should NOT be diluted with water. The original lifespan is 100k miles until it has been serviced and then is 30k miles.

    My personal preferance would be for the factory pink coolant changed every 30k miles. Best part is, although it is more expensive since you don't add water, you don't have to add water. :huh: basically that means no guess work as to the ratio of coolant to water. Simply add more pink until it is full.
     
  10. farrellcsun

    farrellcsun Junior Member

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    Hi everyone: i have an 07 Prius that i got into an accident and they had to replace the radiator. i've had the car back for about a week and noticed the gurgling sound everyone here is talking about. Since the radiator was replaced, i'm pretty sure that is the culprit.

    it doesn't bother me enough to take it back to the dealer right away, so my question is: is it "hurting" anything having those air bubbles in there? do u think it's ok to just wait until the next regular service to have them look into it?

    like someone posted earlier, it may just go away on its own after several weeks. Just not sure how serious it is to look at right away.

    thx! -Farrell
     
  11. Bill Merchant

    Bill Merchant absit invidia

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    Hi Farrell. I'd get it checked out sooner rather than later. Not only is the noise annoying, air is a very poor heat conductor in a liquid-based system. You don't want your car overheating because of bubbles in the system. That was poor work by the people who fixed your radiator. Is your coolant pink? A good repair will have the long-life coolant.
     
  12. farrellcsun

    farrellcsun Junior Member

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    Thanks for the reply. I'll give the dealer a call next week to set up an appt. The work was done by Keyes Toyota, the dealership I got the car from. :-( You would think they would have done or known better. Thx again!
     
  13. bzbee

    bzbee Junior Member

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    Thanks for all the information in this thread. I noticed the occasional "gurgling noise behind the dash" in my 07 Prius. As suggested, checked the coolant it was below low. Topped it up to mid-level, started the car, turned on the heater to max and defrost, revved the engine for a couple of minutes, let it run for about 10 minutes, then revved the engine for a minute. Shut off the car, topped of the coolant to the full mark and closed the tank. Hopefully, the gurgling noise will go away now.
     
  14. edthefox5

    edthefox5 Senior Member

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    Be aware that's the overflow tank your adding coolant too. Sometimes it does not reflect the true coolant level. You have to take the radiator cap off the radiator and check that level. Take the 6 screws out of the black plastic cover on top of the radiator. and remove that cover. With cool engine take the cap off the radiator. if that's low the first leak suspect is a bad water pump seal. Get a flashlight and look real close on the front of the engine by the belt. The belts only job is to turn the water pump. Look for green flecks in that area which is a weeping water pump. If you see green spots that's dried up coolant and the pump is leaking and needs to be replaced. Since you'll be in there replace the pum, belt, and idler pulley if more than 125K miles. Replace the coolant with Toyota SLLC. I use Red Line Water Wetter also as its a good pump lubricant.

    Unless you just had the coolant replaced improperly sounds like you have a bad leak and alot of air has gotten into the system.

    Be aware the only way you'll know if your out of coolant is the engine will overheat and throw an overheat dash alarm. By then its too late for this little aluminum head motor. Motor damage. Poor design no temp gauge.

    Pay careful attention to a low coolant issue and fix asap.

    if you do start a repair I would move your post over to the Gen2 Maintenance forum which is where it belongs.
    Tagging onto a 8 year old thread will become confusing for anyone that wants to follow your post.
     
  15. Kimberly S Prescott

    Kimberly S Prescott Junior Member

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    Weird thing is that I hear a similar “gurgling” noise but I thought it sounds more mechanical, like an HID bulb or the baluster being weird... my Prius is going in for a checkup tomorrow
     
  16. pasadena_commut

    pasadena_commut Active Member

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    Gurgling under the dash was the first sign of trouble on a Mazda we owned that developed a pinhole leak in a coolant line. Initially there were no drips under the car (must have only been leaking when moving for some reason). Eventually it started leaking like crazy, at which point it was obvious what the problem was.

    So, yes air in the system, but that can come from things other than an improper refill.
     
  17. edthefox5

    edthefox5 Senior Member

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    Gurgling under the dash is air in the coolant system. Be careful there as this engine has an aluminum head and an engine over heat could end expensively.

    you don’t know the engine is overheating because there is no temp gauge.

    Getting rid of air lock is very difficult on a G2 as it has a coolant thermos and air tends to get trapped in that bottle and that requires jumping out the thermos pump relay and cycling so it will move that air lock along.

    Based on what we see here the dealer is clueless on how to do this.
     
  18. ChapmanF

    ChapmanF Senior Member

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    Something under the dash that could be called “gurgling” with quotes, but maybe sounds more mechanical, in a Gen 2 or Gen 1 can often be this.

    That thread has a video attachment you can play to compare the sound (and see what's making it).
     
  19. Frontporch

    Frontporch Member

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    I didn't want to start a new thread, but the noise I just started to notice isn't a bubbling sound like I have heard many times with other cars. It sounds like its coming from inside the dash and sounds like a very muffled typing noise. Its erratic, not like the sound of a long buzz... silence buzz... of the coolant pumps. It seems to start up pretty consistently when the motor starts up and I don't hear it much when driving, but its also maybe drowned out by other noises.

    just checked my radiator (full) and overflow (also full) and there was no recent work to the system.

    It sounds a lot like what my Honda Odyssey just went through where a blend door motor stripped its plastic gears. Does the Prius have anything similar?
     
  20. ChapmanF

    ChapmanF Senior Member

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    You sound like someone who really wants to follow the link given above in post #18 and compare your noise to the video that is attached there.
     
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