Is thermos necessary?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Technogeek, Feb 9, 2011.

  1. Technogeek

    Technogeek New Member

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    My 2006 prius has 102,000 miles and the coolant pump for the thermos is getting alarmingly noisy.

    Is it true that only north American Prius cars have the thermos? Would there be any harm in "unplugging" or otherwise disabling the thermos pump? If mine fails soon, I would rather not put in another one as it is a problematic part. So is there any way to remove or disable the thermos in a north American spec prius to make it more like a non NA spec Prius?
     
  2. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    Like the bladder in the fuel tank, the thermos is only needed to make the Prius pass the EPA AT-PZEV standard. So long as your personal ethics and your state inspection laws allow you to pollute without regard to AT-PZEV emission standards, the thermos is not 'needed'.

    If it is any help at all in deciding, without the thermos, your gas mileage will be lower, as the car will take longer to warm up.
     
  3. Hal W

    Hal W New Member

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    Take it in and have Toyota replace it. I think Toyota is replacing the old pumps? Hal
     
  4. seilerts

    seilerts Battery Curmudgeon

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    There is a TSB on this but the pump is a powertrain warranty item (maybe you are referring to the inverter cooling pump?). They are sold at e.g. Champion, Conicelli, etc. for $127 for DIY. Expect to pay, what, $300 at a dealer?
     
  5. Technogeek

    Technogeek New Member

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    Thanks for the feedback. I think the warranty on my car has expired, but I will take it in and find out what Toyota says. I will also have them look at my noisy coolant control valve.
     
  6. JimboK

    JimboK One owner, low mileage

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    Seilerts is correct. There was a TSB issued on the pump but it is replaceable only if the power train warranty (5 years, 60K miles) is still in effect. So yours will not be replaceable under warranty.
     
  7. philmcneal

    philmcneal Taxi!

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    mine doesn't even work anymore :S but is it because of the weather i've been getting (average 0 degrees C?)

    driving long distances (1 and a half hours) or short distances (trips less than 10 km) I just don't hear the pump going anymore :O
     
  8. efusco

    efusco Moderator Emeritus
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    Definately not critical, and I'd be shocked if you noticed a measurable change in FE. I just don't think it makes a realistic difference. If you can find a salvage pump for a few buck on ebay or some place then maybe replace it yourself. No way I'd pay $300 to replace it.
     
  9. The Electric Me

    The Electric Me Go Speed Go!

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    I have an uncle, that is getting older. As he aged? He had dentists slowly remove teeth that became unuseable or painful.

    He now has a smile like a Banjo Player in Deliverance.

    I say fix it. It evidently lasted for upwards of 102,000 miles. Even in slight degrees, I think if you own a Prius then emissions and fuel economy is a big part of the deal.

    Fix it and enjoy another 102,000 miles of Thermos Coolant Heated, fuel efficient, lower emmisions driving.

    Start throwing away teeth because you don't really need them? Pretty soon nobody wants to see you smiling.
     
  10. Patrick Wong

    Patrick Wong DIY Enthusiast

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    I would say the CHRS thermos is more like carrying around 20 lbs above your recommended weight. If you lost that weight you would be healthier and better off.

    However, a defective thermos causes the check engine light to remain on at all times. That would be my major motivation to get the CHRS thermos replaced. Otherwise, if some other engine DTC is logged, you won't know.

    I would suggest trying to get a part from a salvage vehicle if possible (although this may not be easy since it is easily damaged in a front-end accident.)
     
  11. philmcneal

    philmcneal Taxi!

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    haha no i don't notice the mileage hit (probably don't notice it at all if I use the engine block heater when I can) but if the coolant thermos is suppose to work in sub 32F temperatures then I think mine is screwed :( unless it has something to do with the coolant control valve issue?

    if I don't replace it and the car is drivable with no engines codes then I'm game hehe personally after using canview and seeing the difference it makes... (which is NONE imo) I can see why toyota went with the exhaust heat recovery system found in the newer priuses.

    edit: damnit patrick now you got me worried... SHOULD I MIGHT AS WELL REPLACE THE THERMOS AS WELL oh dear lord this big service I got coming up keeps getting larger and larger D: i might as well replace the HV battery while I'm at it !

    just kidding!

    edit2: so far on my list

    engine water pump replacement
    inverter pump replacement (tsb covered)
    transaxle fluid
    oil change
    coolant control valve

    sigh wish i still have my tools :(
     
  12. The Electric Me

    The Electric Me Go Speed Go!

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    Yeah? You've obviously never spent a family get together with my Uncle.

    The Falcon cannot hear the Falconer. Things fall apart, The Center cannot hold.

    I still wish my uncle would just get dentures, and I'm still going to recommend the OP fix,- instead of deteriate.

    His Prius might be slouching towards the junkyard...but I see no reason to hasten the experience.

    Plus even within your parameters...there is reason to replace.
     
  13. philmcneal

    philmcneal Taxi!

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    ^ i hate to be a cold sore, but to recoup the mileage benifit of 500 bucks from the fuel economy benifit is going to take a LONG LONG LONG LONG LONG LONG LONG LONG LONG LONG


    ... Time, I rather save that money and buy a salvage HV battery so I don't drive some retarded Subie BRZ as my next car and still run on this putt putt prius :)
     
  14. The Electric Me

    The Electric Me Go Speed Go!

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    Hey...no problem. Ultimately it's your vehicle, your call.

    You are not the first person to tell me my opinion was worthless, and I suspect you won't be the last.

    I also admit? I'm somewhat compulsive. The deteriation in of itself bothers me. Like does the picture need to be straightened? No...but I'll straighten it anway...

    I know I'm fighting a losing battle...but I'm going to fight it anway.

    I mean, if you REALLY wanted to keep the thermos...you wouldn't be asking if it was necessary to start with....

    I think the answer appears to be...you can survive without it. The wisdom in doing so, is probably subjective to the individual.
     
  15. philmcneal

    philmcneal Taxi!

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    it is just a cost efficiency ratio that's all, if I can fix it within my means I will just like how you can't stand some things being left being broken like that.

    But for a car like mine 2004 and has high mileage sometimes it is just not worth it you know? Like your uncle as an example you want new dentures for him, but perhaps he feels that he is too old to make the new ones worth it for his age? No offense for the elderly but if I was his age I'd tell my family to take that money and spend it on something nice, if eating and pain wasnt a problem for my teeth (assuming it is all cosmetic)

    I'm just doing reasearch if the thermos being broken causes a driveabiity problem (and in my case it isn't) even though I have no check engine lights currently but not having the thermos go off makes me wonder what's going on with the unit?

    With all that said If I'm lucky I'll find a salvage unit.
     
  16. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Yes, I understand that concept. It is reasonable to compare the benefit to the cost associated with a given repair.

    There is no driveability issue caused by the thermos not working.

    However, in your case if the engine coolant control valve is not working then the engine ECU should log a DTC and the check engine light should come on.

    If the check engine light is intermittently coming on, that might indicate that the coolant control valve also is working intermittently.
     
  17. Britprius

    Britprius Senior Member

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    I have know personal experience of thermos problems along with fuel tank bladders and think myself lucky I live on the other side of the pond where we do not have these dubious extras. But legalities apart there seems little or know advantage from having the thermos from an MPG point of view. The fuel saved against the extra fuel used from dragging the extra weight around must be very marginal, and the amount of emissions saved by the fuel tank bladder is probably insignificant compared to the amount of fuel belched out over the floor.
     
  18. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    I am amused how a known price of $137 became $500 without any facts.
     
  19. philmcneal

    philmcneal Taxi!

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    ok well odd this morning i drove a short distance then stopped and heard the thermos :S when waiting for someone but the weather was 3 degrees C so i guess in sub temperatures it does not want to work!

    nope patrick no CEL light yet ever! don't jinx me haha
     
  20. Mar_07

    Mar_07 New Member

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    this thread reminds me of somthing.. :D:D
     
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