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Prius, overheating P1150. Coolant loss. Replaced Everything

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by BillS., Jun 24, 2016.

  1. BillS.

    BillS. New Member

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    I am getting a P1150 code on a 06 Prius (240k). Red Triangle and temp light come on after about 15min of driving (no heat). I have taken it to the dealer. They said the Coolant control valve (stuck) and waterpump (leaking) needed replacing. I replaced both of these myself along with the temp sensor and radiator cap, but the problem persisted. Coolant is also shooting out of the overflow hose in the reservoir tank when car warms up. I just took it to a different shop yesterday because I was assuming I could not get all of the air bled out of my system. They charged me $200 and said there was quite a bit of air in the system. The first thing I did when starting my Prius was to check the heat, no heat. I drove it home and immediately noticed there was yet again coolant spitting out of the overflow tube. I didn't want to believe this was happening again. I drove it to work this morning (15min drive) and the red triangle and temp light came back on. Please help me. I have spent 3 weeks working on this and $500.

    I now have been driving it with the radiator cap loose so the pressure does not build up and spit the coolant out. This works for short drives, but I've noticed my coolant is disappearing quickly. No visible coolant on the ground or anywhere in the engine bay.
     
    #1 BillS., Jun 24, 2016
    Last edited: Jun 24, 2016
  2. JC91006

    JC91006 Senior Member

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    I think you have a blown head gasket, pull out the oil dipstick and see what level it's at. If it's way over the full line, then you've found your missing coolant. Also the oil will look very milky

    You cannot drive with the radiator cap loose.........that's just crazy
     
  3. BillS.

    BillS. New Member

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    Thanks for your response. I have checked the oil over the past 4 weeks (since this started) and it has looked fine (color & level). I also had the head gasket tested by a reputable shop.
     
  4. JC91006

    JC91006 Senior Member

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    I'm unsure how you're getting so much air in the system.
     
  5. JC91006

    JC91006 Senior Member

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    Have you tested the radiator cap? Make sure it doesn't allow air to enter?
     
  6. BillS.

    BillS. New Member

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    I forgot to add that to the list. I did change the radiator cap. That was the first thing I did.
     
  7. 69shovlhed

    69shovlhed Surly tree hugger

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    there is a way to test for a blown head gasket with a special tester that looks sort of like a turkey baster with blue liquid in it. you hold the tool over the open radiator and squeeze the bulb, which sucks in vapor from the radiator. if there is exhaust gases in the radiator the fluid will turn green and then yellow.
    but from what you describe, i believe you have a blown head gasket between the water jacket and one or more cylinders. that's why its pushing so much pressure out of the overflow.
     
  8. BillS.

    BillS. New Member

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    I took the car back to the Toyota dealer yesterday. I listed off everything I replaced and told them to figure out what's going on. They tested the head gasket (again), and it was fine. They called me a few hours later and said my radiator itself is actually leaking. I'm not sure i totally believe them since I have been looking at the radiator on a daily basis for the last month and a half trying to locate a leak. I'll go pick up a radiator for $100 and give it shot I guess.
     
  9. Augustus88

    Augustus88 Junior Member

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    I doubt that the radiator is the problem. It does sound like combustion gasses are exiting the cylinders and entering your coolant system, which would cause high temps and shooting out coolant as the cap opens to relieve pressure.

    May want another shop to check it.
     
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  10. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Why not ask to be shown where the leak is, so that you don't need to guess.
     
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  11. BillS.

    BillS. New Member

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    Hi Patrick. I would have, but by the time I got back to the dealer to pick it up, they were closed. Yesterday was Sunday so they were closed as well.

    Yesterday evening I zip-tied an empty beer bottle into the engine compartment and stuck the overflow tube into it. I wanted to stop the coolant from leaking out of there. When I went outside this morning I checked the bottle and it was about half full, but there was coolant on the ground. Maybe this means i DO have a leak coming from somewhere (the radiator like the dealer said??)
     
  12. Augustus88

    Augustus88 Junior Member

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    If you have a way to safely jack the car up, you can test yourself.

    Set the heat to full blast, that should force the engine to run more. You can then look around inside the bay while the engine is running, looking for the leak source.

    Also, the radiator cap is designed to keep some pressure in the system. If the system cannot build up pressure, the boiling point of the coolant will be lower, resulting in more boiling and water shooting into the overflow tank. The cap is designed to open at 16 psi and vent excess pressure.
     
  13. Toppcat

    Toppcat Member

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    Ok you got lots of good advise ! Sound like 1st radiator cap, thermostat, head gasket either check oil contamination or coolant in oil if none pull spark plugs coolant wil clean off spark plugs, I'd so pulling the heads note the torque on each head bolts or nuts, this will idea if you have a failed bolt \stud, check visually for cracks in the head and each cylinder walls if none is found, it need to be sent out to a shop which has a process to detect micro cracks! Most likely this could be costly repair! Also check your exhaust pipe outlet if it's clean it burning coolant note if the exhaust gas feels wet!
     
  14. BillS.

    BillS. New Member

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    After having 3 technicians look at my head gasket and saying it's fine, I'm going to rule it out for now. If the radiator is leaking is it possible that my system is sucking in air, thus causing the clog along with the leak? I just read this below thread about the filler neck leaking where it meets the radiator itself. I am going to inspect this tonight:

    Leak by coolant filler pipe - 2005 | PriusChat

    PS: The one thing I haven't checked is the thermostat.
     
  15. M in KC

    M in KC Active Member

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    If liquid can escape, air can enter. Run down to your local parts house and check-out one of their coolant system pressure testers through their loan-a-tool program. You will find your leak(s) in minutes.
     
  16. BillS.

    BillS. New Member

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    Well, my radiator arrived last week and I installed it on Saturday (not fun). Needless to say, this was also not my problem. I could see where the Toyota dealer said my radiator was leaking, but it was just some tiny build up. I topped off the coolant after install, did my best bleeding the air out and drove it around for about 45min. It was fine, until the following morning. This is what keeps happening to me. After I top off the coolant in the radiator cap side the car runs fine because there is coolant in the radiator. By the time the next day rolls around then there's no longer coolant in the radiator and my light comes back on. Now I have changed almost everything in this system except for the thermostat. I'm so frustrated at this point I just want to trade it in for nothing.
     
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  17. JC91006

    JC91006 Senior Member

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    The radiator drained completely? Or you just have to add a little? I normally have to add to the radiator a few times before all the air is out of the system.
     
  18. BillS.

    BillS. New Member

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    Right. I run it for a little bit with heat on max, add more coolant, squeeze hoses....repeat etc
     
    #18 BillS., Jul 5, 2016
    Last edited: Jul 5, 2016
  19. Augustus88

    Augustus88 Junior Member

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    Is there ANY sign of leakage, other than the decreasing coolant level? On the ground? From the heater core? Anything?

    If not, then the only possibility is that the engine is consuming the coolant through a failed gasket. You said the shop said the head gasket was good... Maybe get a second opinion or test it yourself?
     
    BillS. likes this.
  20. BillS.

    BillS. New Member

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    Well, finally it was confirmed that it's a head gasket. The engine combustion is actually leaking into my coolant thus causing the coolant to push out through the overflow tube (Augustus88 was right). I cannot afford to have anyone do this job for me $2000+ for a car with 240k. I have it decommissioned for the time being as I try to decide what to do with it. I was thinking about topping it off with coolant and trying to trade it into a dealer? Otherwise I'd just have to donate it and hope I get some money back from the government at the end of the year.

    Is this is really hard job to try to do myself? Touching the electric motor kind of scares me. Should I maybe try some sort of head gasket sealer like Steel Seal? I know this probably won't work, but worth a shot? All in all, I spent about $750 in parts and diagnoses just to get to this point. Any suggestions would be greatly appreciated.