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07 prius check engine light. need to bleed the air in the coolant?

Discussion in 'Gen 2 Prius Technical Discussion' started by cdsjklee, Sep 15, 2008.

  1. Patrick Wong

    Patrick Wong DIY Enthusiast

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    I actually just let the fluid come out of the radiator bleed valve because I'm not expecting to let much out. To be ecological and economical though, my guess is that 3/8" ID hose would work.

    I think you should just buy a length of each of the various hose sizes available at your discount auto parts store because you'll eventually come up with some use for the hoses...
     
  2. danimelara

    danimelara Junior Member

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    Sorry for reviving this old thread.

    I have tried to bleed the coolant like 3 times already and the noise persists.

    Is there any other reason why the Prius 2006 would make a noise behind the dashboard?
     
  3. bisco

    bisco cookie crumbler

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    are you using tech stream?
     
  4. dolj

    dolj Senior Member

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    Have you checked the tray under the wipers, if leaf debris are blocking the drain holes, water can collect there. Typically you only hear it if you accelerate off, or turn left or right. Usually, it occurs only after it has rained, if this is the problem.
     
  5. Patrick Wong

    Patrick Wong DIY Enthusiast

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    1. What was your method to drain, replace and bleed the engine coolant?
    2. What is the nature of the noise you are hearing?
    3. Does that noise occur only when the cabin heater is running, or not?
     
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  6. danimelara

    danimelara Junior Member

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    1. I recently changed the water pump and belt and drained the entire coolant. I replaced the coolant with the Toyota brand pink fluid. I keep refilling the radiator and reservoir until it couldn't hold any more fluid.
    During the original refill, I opened the bleeder and used as hose as you recommend. I noticed that the fluid was passing thru the hose to the radiator and it was bubbling. The first week after the original bleed the car didn't make any noise. After a week the car started making the noise again.
    I did another bleed about a week ago. I noticed that this time fluid wasn't passing thru the hose into the radiator. I thought that it was weird. Occasionally the hose would show some signs of fluid passing thru and sometimes it would be just air (bubbles).
    Last night I did it again and again, just air and some bubbles but the fluid wasn't passing thru the hose. I drove the car after that and it seemed fine, No funny noises. This morning again the noises started as soon as i got into the car.
    What am I doing wrong? I followed your instructions to the dot on how to bleed the air, but it does not seem to work.

    2. The noise sounds like gurgling. like a hollow bubbling sound inside a hose or tube. It is directly behind the steering wheel

    3. The sound occurs all the time, especially when the wheather is cold. Sometimes it happens as soon as the car is on (even before the ICE starts). I can hear it the most when the car is at a stop light (ICE not running)

    -Thanks to the other posters that took the time, however I do not think that there's any leaves in the tray underneath the wiper.

    -I do not know what Tech Stream is. how would this help me?

    thanks.
     
  7. Patrick Wong

    Patrick Wong DIY Enthusiast

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    1a. When you drained the engine coolant, which drain cocks did you open? If you opened the drain cock at the coolant heat recovery canister, did you run the CHRS pump to refill the canister?
    1b. When you were bleeding the air out of the engine coolant system, did you have the cabin heater set to MAX HEAT, fan set to maximum speed, and rev up the engine continuously for 10 minutes or more? Does the cabin heater work well in produce heat?
    2. Do you think that there is air bubbling in the cabin heater core? The heater core is located on the passenger side of the dashboard.
    3. Does the gurgling noise occur even when the cabin ventilation system is turned off?

    If you have any warning lights on (check engine light for example) then diagnostic trouble codes will be logged. In that case, use Mini VCI (which is a pirated form of Toyota Techstream) to retrieve the DTC so that you will have a further clue about what is wrong with your car.
     
  8. danimelara

    danimelara Junior Member

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    Thanks Patrick for your expertise.

    1a. I drained the fluid by opening the valve that is located on the front driver's side (the one next to the front tire). I refilled the system by puting fluid into the radiator, and yes I ran the heat and fan to the max when doing so.
    1b. After puting the car in "problem mode", I turn on the fan and the heater to the max when bledding the air. Hot air was being produced by the heater. I didn't know that I had to REV the engine for 10 minutes. Do you mean that besides puting the car in the "problem mode" I have to manually REV the engine by pressing the gas pedal?
    2. The sound comes from the Driver side, from the MDF to the left. The sound comes from behind the steering wheel.
    3. The noise occurs even when the heater is off. I almost never use my heater since I live in southnern California and the minimum tempature is about 55F.

    I forgot to mention that there's no "check engine" light on.
     
  9. Patrick Wong

    Patrick Wong DIY Enthusiast

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    1a. OK, since you had drained the coolant at the CHRS canister drain cock, you need to run the CHRS pump a few times to make sure that engine coolant has completely filled the canister. By now the canister may already be at least partially full because the pump runs a few seconds upon startup and shutdown, but this should be checked to ensure the canister is totally full. In my post about how to replace engine coolant, it discusses how to find the CHS relay (in the relay box mounted to the cowl tray housing the windshield wiper motor) and how to identify the relay switched terminals. The concept is to short the terminals in the relay socket which correspond to the switched terminals, to manually run the CHRS pump. Do this for 10 seconds at a time and see whether the engine coolant level in the radiator (not the overflow reservoir) drops. If it does, fill to the top of the radiator neck with Toyota SLLC. If the engine coolant level does not drop then the canister presumably is full.
    1b. Yes, you need to rev up the engine as fast as possible, which is only going to be around 3,000 RPM when the shift selector is in P, so that you can circulate the engine coolant more quickly and get air out of the system. Also, squeeze the radiator hoses a few times to further encourage trapped air out of the system.
    2. There is nothing behind the steering wheel which would cause a noise, that I am aware of. The only moving parts back there would be the steering wheel column, so if you hear a noise associated with turning the steering wheel, that would probably be related to the steering gear or steering column. There is no plumbing.
    3. Is it possible that the noise is coming from the CHRS system located in the driver's side front fender?
     
  10. danimelara

    danimelara Junior Member

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    I will try to run the CHRS pump tonight when I get home. I read the original posting on how to change the coolant, however I am still a little bit unclear about how to manually run the CHRS. Do you have a graphic description, video, photos or diagram on how to do the paperclip trick?
    Should I open all the bleeder valve, as well as the radiator and reservoir while running the CHRS?

    thank you for all your help.
     
  11. Patrick Wong

    Patrick Wong DIY Enthusiast

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    You do not need to open the bleeder valve. Just have the radiator cap off so you can see the extent to which the fluid level drops in the radiator.

    You will need an ohmmeter to measure resistance across the relay terminal pins. There are two pairs of terminal pins. One pair is for the relay coil and will measure ~100 ohms. The other pair is for the switched terminals and will read infinite resistance.

    Note how the relay pins plug into the relay socket, and identify the socket terminals that mate with the relay switched terminals pins. You will place the paper clip across those two terminals in the socket, in order to force the CHRS pump to run.

    The car should be IG-OFF while you are running the CHRS pump. Do not run the pump more than 10 seconds at a time, then let a little time elapse so the pump can cool off.
     
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  12. Ayan

    Ayan New Member

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    Hello guys.
    i own Japanese import gen 3 prius 2010, i have problem with the coolant overheating which was replaced couple of days ago due to blown radiatoe hose. now the coolant fluid over heats in matter of few minutes and have a cold cabin heater. I strongly suspects that this due to to air pockets in the circulation, please advice how to bleed it. only air bleed valve i found so far is with white cap in the picture.
     

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  13. ydpplqbd

    ydpplqbd Active Member

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    Thanks!!! Had a P1121 code. I changed out the Coolant Flow Control Valve. Now I need to bleed the radiator. Your write-ups are excellent!!!!