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Overheating after changing cap, coolant, and thermostat

Discussion in '1st Gen Tundras (2000-2006)' started by Squire343, Jun 15, 2025 at 4:24 PM.

  1. Jun 15, 2025 at 4:24 PM
    #1
    Squire343

    Squire343 [OP] New Member

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    I was driving my truck and it threw a check engine light, code P0117. Shortly after truck overheated I immediately pulled over and turned it off. Towed it home and drained the coolant which appeared to be mostly water (I got the truck a few weeks ago). Drained coolant from the radiator and reservoir, filled with new coolant, replaced the thermostat and radiator cap.
    Truck still overheats after idling about 10 minutes and I found this gargling from the reservoir in the attached video. oil looks normal, no steam from tail pipe. Any advice is appreciated.
     

    Attached Files:

  2. Jun 15, 2025 at 4:28 PM
    #2
    Jack McCarthy

    Jack McCarthy Working remotely from the local pub

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    Missed your comment on the new thermostat. Was it clocked correctly according to the FSM (field service manual) when installed? That’s important.
     
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  3. Jun 15, 2025 at 4:30 PM
    #3
    1lowlife

    1lowlife Toxic prick and pavement princess..

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    I'm not a mechanic but googling 'code P0117' points to a possible Engine Coolant Temperature (ECT) sensor issue.
    What year is your Tundra?
     
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  4. Jun 15, 2025 at 4:32 PM
    #4
    blackdemon_tt

    blackdemon_tt Battery Slayer

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    There is air in the system. You will need to reburp the system. Cabin heater and defroster on, full blast. Make sure you lift the front. If it overheats turn off wait 5 minutes and restart again.
     
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  5. Jun 15, 2025 at 4:39 PM
    #5
    Squire343

    Squire343 [OP] New Member

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    I’m not sure what that means I’m sorry. I bought a new thermostat at AutoZone and installed it. Seemed straight forward to me but are you saying there’s something I should check?
     
  6. Jun 15, 2025 at 4:40 PM
    #6
    Squire343

    Squire343 [OP] New Member

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    it’s a 2005 V8. The check engine cleared itself after I put more coolant in. I read that low coolant can throw that code.
     
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  7. Jun 15, 2025 at 4:41 PM
    #7
    Squire343

    Squire343 [OP] New Member

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    ok I was thinking maybe that was a problem. I notice that when I turn the heater on it’s not hot anymore. I can’t see how this would be related but it’s weird that it just started doing that …
     
  8. Jun 15, 2025 at 4:49 PM
    #8
    jerryallday

    jerryallday New Member

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    You need to burp the coolant (get all the air out). It takes a couple of heat cycles to get all the air out correctly. You can YouTube a video.
     
  9. Jun 15, 2025 at 4:52 PM
    #9
    Jack McCarthy

    Jack McCarthy Working remotely from the local pub

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    1lowlife likes this.
  10. Jun 15, 2025 at 5:00 PM
    #10
    ATBAV8

    ATBAV8 New Member

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    Yes. Thermostat orientation is important. There is a "jiggle pin" that needs to be at the highest point. The FSM will show this.
     
  11. Jun 15, 2025 at 5:08 PM
    #11
    Squire343

    Squire343 [OP] New Member

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    Jack McCarthy[QUOTED] likes this.
  12. Jun 15, 2025 at 5:09 PM
    #12
    Squire343

    Squire343 [OP] New Member

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    Yes I put it right at the top. Thanks for clarifying
     
  13. Jun 15, 2025 at 5:10 PM
    #13
    Jack McCarthy

    Jack McCarthy Working remotely from the local pub

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    Then the only thing remaining is to bleed the air out correctly.
     
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  14. Jun 15, 2025 at 5:17 PM
    #14
    Jack McCarthy

    Jack McCarthy Working remotely from the local pub

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    That usually indicates the coolant isn’t circulating.
     
  15. Jun 15, 2025 at 5:24 PM
    #15
    ATBAV8

    ATBAV8 New Member

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    When did you notice it's not hot? After you changed the thermostat and coolant, or before? The reason I ask is because if there was no heat before, you might have a circulation problem, which would point to the water pump. Do you know what the status of the timing belt and water pump is? Like when it was changed last?
     
  16. Jun 15, 2025 at 5:37 PM
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    Redoak

    Redoak New Member

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    Heck no on thermostat from anyone but aisin, or Toyota.

    I went through that years ago on a Malibu.
    Started getting hot replaced water pump, thermostat etc.
    Got hot again 2 days later and blew head gasket had to have heads redone.

    3 more times it happened. Finally figure out all the thermostats I was getting were sticking half open, by dropping them in boiling water.
    And I wasn’t getting the cheap thermostats.
    Gave up on that vehicle cause costing to much to keep redoing heads.
    I know that was years ago, but it ruined me getting thermostats from any chain outfit.
    Also had a new one stick on a truck I had and installed at same time as the Malibu was having issues.

    Not saying that’s your issue, but definitely where i would start.

    Also if anyone has ever mixed antifreeze it can cause a coagulation that can effect a thermostat working properly by getting in the working piston. Needs to be thoroughly flushed before installing a new thermostat.
     
    Last edited: Jun 15, 2025 at 5:46 PM
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  17. Jun 15, 2025 at 5:53 PM
    #17
    MadMaxCanon

    MadMaxCanon New Member

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    When you begin to overheat its very important to turn your heater on full blast immediately to lower temps. All you have to do to burp your system is turn heat on while idling and watch your radiator coolant until bubbles stop coming out. And squeeze your top radiator hose a few times.
     
  18. Jun 15, 2025 at 6:42 PM
    #18
    Squire343

    Squire343 [OP] New Member

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    The first thing I did was change the coolant and it was after that I noticed the heater wasn’t working. I know that you’re supposed to blast the heat while letting it idle after changing coolant so that’s how I found out the heater wasn’t working

    when I had the truck looked at by a mechanic shortly after purchasing, he said the timing belt looked fairly new. Can’t say anything about the water pump
     
  19. Jun 15, 2025 at 6:42 PM
    #19
    Squire343

    Squire343 [OP] New Member

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    Ok that’s good advice. I’ll try to return that thermostat and get a higher quality one
     
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  20. Jun 15, 2025 at 6:43 PM
    #20
    Squire343

    Squire343 [OP] New Member

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    This could be because of air being in the system, correct?
     
  21. Jun 15, 2025 at 6:52 PM
    #21
    1lowlife

    1lowlife Toxic prick and pavement princess..

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    Please post your results so others can learn.
    Also, I'm curious about the remedy...:confused::cool:
     
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  22. Jun 15, 2025 at 6:56 PM
    #22
    Redoak

    Redoak New Member

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    You can test that one.
    That should be a 180 if I remember right.
    Drop it in pan of water at 190 and see if it opens.
    I'd still get a better one though. That's another one of those things to never cheap out on.
     
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  23. Jun 15, 2025 at 7:41 PM
    #23
    Squire343

    Squire343 [OP] New Member

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    Redoak[QUOTED] likes this.
  24. Jun 15, 2025 at 8:11 PM
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    ATBAV8

    ATBAV8 New Member

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  25. Jun 16, 2025 at 4:15 AM
    #25
    NickB_01TRD

    NickB_01TRD You don't need less cars, just more driveway.

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    What are you going off of to say the truck is overheating. The gauge being up near the H or actual overheating symptoms? The gauge and the ECU have different sensors. (Or did that stop in the VVTi days? @shifty` )

    Also what coolant are you running? The proper Toyota pink or just generic green/yellow?
     
  26. Jun 16, 2025 at 6:53 AM
    #26
    shifty`

    shifty` Like Fred Flintstone, drivin around with bald feet

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    Only ‘00-04 (pre-VVTi) had the two ECT sensors side-by-side above the t-stat/on the passenger side of the throttle body.

    I sorely hope OP isn’t using anything except pink SLLC for his coolant. That would really suck if he fell into the “universal coolant” trap.
     
  27. Jun 16, 2025 at 7:19 AM
    #27
    Redoak

    Redoak New Member

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    And mixing certain types of coolants is a big no no!
    I’ve seen them coagulated, clabber years ago from doing so.
    Takes a lot of flushing to clean that mess out of system too.
     
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  28. Jun 16, 2025 at 7:35 AM
    #28
    Squire343

    Squire343 [OP] New Member

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    the gauge is going high, and the radiator is steaming when I lift the hood.
    I’m using pink pre mixed coolant
     
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  29. Jun 16, 2025 at 7:36 AM
    #29
    Squire343

    Squire343 [OP] New Member

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    I’m using pink pre mixed coolant. It’s an 05 but given what you said about the sensors, I don’t think it’s just the gauge. Seems like the truck is actually overheating.
    Big fan btw I’ve read so many of your threads lol
     
  30. Jun 16, 2025 at 9:07 AM
    #30
    KNABORES

    KNABORES Sarcasm incoming

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