1. Welcome to Tundras.com!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Tundra discussion topics
    • Transfer over your build thread from a different forum to this one
    • Communicate privately with other Tundra owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

How many of you are bypassing the coolant on your throttle body?

Discussion in '2.5 Gen Tundras (2014-2021)' started by 00h2itr, Feb 21, 2025.

  1. Feb 21, 2025 at 6:45 AM
    #1
    00h2itr

    00h2itr [OP] New Member

    Joined:
    Jan 13, 2025
    Member:
    #128779
    Messages:
    269
    Gender:
    Male
    Carolina's
    Vehicle:
    21 Limited CM TRD-OR
    Clearly Keith with Dirty Deeds is a fan. Having read a bit more on this, the MAF reads and adjusts before the TB, and with the velocity of the air going into the TB, it might be a moot point, but less heat is better, right?

    I live in upstate, SC. So while it does snow on occasion, it's not like Denver, Michigan or god forbid Montana like our friend @memario1214

    So what says you? I'll be under the hood anyway in the coming weeks as well as installing the Stillen TruPower I was conned into by you jerks. Worth just doing this while I'm there?
     
    HulkSmurf14 likes this.
  2. Feb 21, 2025 at 7:15 AM
    #2
    memario1214

    memario1214 Hotshot Offroad Staff Member Vendor

    Joined:
    Dec 13, 2015
    Member:
    #2252
    Messages:
    12,656
    Gender:
    Male
    First Name:
    Colton
    Missoula, MT
    Vehicle:
    '21 Limited MGM CrewMax
    I've not taken a deep dive into internals on this truck, but now my interest is piqued... Is this just a goal of reducing charge temps?
     
  3. Feb 21, 2025 at 9:15 AM
    #3
    Danman34

    Danman34 New Member

    Joined:
    Sep 19, 2018
    Member:
    #19579
    Messages:
    2,639
    Gender:
    Male
    First Name:
    Danny
    Vehicle:
    2018 White Tundra TRD Sport
    My iats are the same as ambient while driving. If decreasing intake temp is the reason, im not convinced.
     
  4. Feb 21, 2025 at 9:37 AM
    #4
    00h2itr

    00h2itr [OP] New Member

    Joined:
    Jan 13, 2025
    Member:
    #128779
    Messages:
    269
    Gender:
    Male
    Carolina's
    Vehicle:
    21 Limited CM TRD-OR
    I believe that is correct. But the MAF is before TB closer to intake box and is responsible for A/F I believe so I'm not sold
     
  5. Feb 21, 2025 at 9:44 AM
    #5
    armyoffoo

    armyoffoo Member

    Joined:
    Jun 4, 2018
    Member:
    #15876
    Messages:
    1,267
    Gender:
    Male
    First Name:
    Bryan
    Cypress, TX
    Vehicle:
    2018 Black TRD Sport CrewMax
    Supercharged with all the trimmings
    Most of the people with superchargers reroute the coolant around the TB, with the coolant temps getting to 190+ degrees, it's not cooling anything.
     
  6. Feb 21, 2025 at 10:06 AM
    #6
    snivilous

    snivilous snivspeedshop.com

    Joined:
    Apr 16, 2019
    Member:
    #29192
    Messages:
    4,755
    SW UT
    Vehicle:
    300k+ Supercharged 2008
    Waste of time imo, but a 190deg throttle body certainly isn't helping the engine either.
     
  7. Feb 21, 2025 at 12:30 PM
    #7
    Saltyhero13

    Saltyhero13 Throbbing Member

    Joined:
    Aug 12, 2020
    Member:
    #50704
    Messages:
    4,893
    Fuel delete mod Cup holder upgrade
    ~1% HP gain per 10* of temp drop is the rule of thumb. Not sure what it means on NA set ups.
     
  8. Feb 21, 2025 at 12:42 PM
    #8
    TacomaTRD4x402

    TacomaTRD4x402 New Member

    Joined:
    Nov 26, 2023
    Member:
    #107483
    Messages:
    1,460
    Gender:
    Male
    Southern California
    Vehicle:
    '18 Tundra TRD Sport 2WD 5.7 Crew Cab MGM
    I'm in Southern Cali where it never snows or gets anywhere below 40° so I bypassed mine just for f sakes. I can't really say there's noticably high performance gains from it. Also I didn't do any testing or readings since at the time I didn't have the Scangauge that I have now but it's such an easy mod with no negative consequences (unless your in freezing temps) I figured, eh why not.

    Edit:
    Not sure if you came across this thread yet but
    @Silver17 did some testing here..
    https://www.tundras.com/threads/tundra-throttle-body-coolant-bypass-mod.118879/#post-3555871
     
  9. Feb 21, 2025 at 1:07 PM
    #9
    00h2itr

    00h2itr [OP] New Member

    Joined:
    Jan 13, 2025
    Member:
    #128779
    Messages:
    269
    Gender:
    Male
    Carolina's
    Vehicle:
    21 Limited CM TRD-OR
    yep, had found that. I assume this may be more popular with the S/C crowd. I think I'll let it be for the time being. Just paused to consider it as I will be installing the Stillen intake next week.
     
  10. Feb 21, 2025 at 3:39 PM
    #10
    Ericsopa

    Ericsopa Old man and the sea

    Joined:
    Nov 7, 2015
    Member:
    #2069
    Messages:
    1,501
    Gender:
    Male
    First Name:
    Mike
    N of Rio Grande, S of Red, E of Pecos, W of Sabine
    Vehicle:
    2013 Tundra CrewMax TRD Ltd Super Duper White OVtuned
    Did the bypass on mine a couple years ago. Usually mild here in the winter (but was 12° yesterday morning :eek:) and the summers are hot. Don't know that it's helped anything, but it hasn't caused any problems.
     
    Wynnded likes this.
  11. Feb 21, 2025 at 3:42 PM
    #11
    centex

    centex New Member

    Joined:
    Nov 27, 2022
    Member:
    #87464
    Messages:
    1,918
    Gender:
    Male
    I did it out of boredom.
     
    blanchard7684 likes this.
  12. Feb 21, 2025 at 3:48 PM
    #12
    _none_

    _none_ Poser

    Joined:
    Mar 23, 2023
    Member:
    #94306
    Messages:
    459
    Vehicle:
    2020 DC SR5 4x4
    Waste of time.
     
    Rodtheviking likes this.
  13. Feb 21, 2025 at 3:58 PM
    #13
    AZBoatHauler

    AZBoatHauler SSEM#140 / 2.5 gen plebe

    Joined:
    Aug 13, 2019
    Member:
    #34576
    Messages:
    9,040
    Gender:
    Male
    First Name:
    Adam
    So.Arizona
    Vehicle:
    2017 CrewMax 4x4, 2017 LandCruiser, 2005 Sequoia 4x4
    Demello / SOB Fab Bumpers, SuperWinch, WKOR sliders, RCI skids, Baja Designs lighting, Billy 6112 and 5160 w/ CB +2, JL Audio with Alpine HU, DD 10" Exhaust, LED headlights, Rago fab mounts, 35” BFG, HAM radio
    You might be the best person to ask - I have a 165 degree thermostat sitting on my shelf from Mishimoto. I’ve been reluctant to install it because I’ve read the truck will not get warm enough to enter its normal ECU programming essentially always staying in a state of “warm up” mode…

    Do you have an opinion?
     
    Wynnded and FrenchToasty like this.
  14. Feb 21, 2025 at 4:04 PM
    #14
    snivilous

    snivilous snivspeedshop.com

    Joined:
    Apr 16, 2019
    Member:
    #29192
    Messages:
    4,755
    SW UT
    Vehicle:
    300k+ Supercharged 2008
    There's a number of ECM features that don't become active until 182deg (in stock form), ie that's when the truck thinks it has warmed up. So there is merit to your idea. If your truck runs hot to begin with, then the cooler thermostat MIGHT drop the temperatures a bit and stay above that 182deg threshold. If the trucks normal operating temp is in the 190-200deg zone it's debatable if it's worth doing, or even be detrimental.
     
  15. Feb 21, 2025 at 6:58 PM
    #15
    _none_

    _none_ Poser

    Joined:
    Mar 23, 2023
    Member:
    #94306
    Messages:
    459
    Vehicle:
    2020 DC SR5 4x4
    What are you trying to achieve with a lower temp thermostat? These trucks don’t run hot like the ecoboost f150 do.

    low temp thermostats used to be the trick way back or a way to mask an overheating issue.
     
  16. Feb 21, 2025 at 7:08 PM
    #16
    AZBoatHauler

    AZBoatHauler SSEM#140 / 2.5 gen plebe

    Joined:
    Aug 13, 2019
    Member:
    #34576
    Messages:
    9,040
    Gender:
    Male
    First Name:
    Adam
    So.Arizona
    Vehicle:
    2017 CrewMax 4x4, 2017 LandCruiser, 2005 Sequoia 4x4
    Demello / SOB Fab Bumpers, SuperWinch, WKOR sliders, RCI skids, Baja Designs lighting, Billy 6112 and 5160 w/ CB +2, JL Audio with Alpine HU, DD 10" Exhaust, LED headlights, Rago fab mounts, 35” BFG, HAM radio
    Just trying to make things easier in our brutal summers. I use the truck to tow a boat up and down 8% grades in 120 degrees.

    Highest temps I’ve see were around 212 working it hard. Anything under 80 degrees out unladen and it runs right at 185.
     
  17. Feb 21, 2025 at 7:36 PM
    #17
    lr172

    lr172 New Member

    Joined:
    Sep 27, 2024
    Member:
    #123527
    Messages:
    253
    Gender:
    Male
    Vehicle:
    07 DC
    Coolant in the tb is not there to cool anything. It is there to warm up the intake air. They do this for economy. The warmer the air, the better the atomized fuel will mix with the air. The better it mixes, the further lean you can go without a performance hit. This is one of the benefits of direct injection. For max power, you want the densest air possible and that means cold. Great for a hot rod, not so great for a vehicle you drive to work.
     
    KNABORES likes this.
  18. Feb 21, 2025 at 7:52 PM
    #18
    snivilous

    snivilous snivspeedshop.com

    Joined:
    Apr 16, 2019
    Member:
    #29192
    Messages:
    4,755
    SW UT
    Vehicle:
    300k+ Supercharged 2008
    I wouldn't worry about it. My engine has seen similar and higher temperatures plenty of times when I go down the hill where it can be 110+ too, and/or hanging out in boost for awhile. 212 isn't that bad, 220 is my mark where I start to back off and don't want to exceed it. That still leaves ample headroom that the engine could get hotter and still be fine. As long as you monitor your temps when towing which obviously you do, I wouldn't sweat it or swap the thermostat personally.
     
    Wynnded and AZBoatHauler[QUOTED] like this.
  19. Feb 22, 2025 at 5:48 AM
    #19
    HulkSmurf14

    HulkSmurf14 ...Weighted Average...

    Joined:
    Aug 9, 2019
    Member:
    #34377
    Messages:
    2,553
    Gender:
    Male
    Vehicle:
    2014 Tundra Limited
    Tastefully enhanced...
    I did this last summer and through our winter hitting -32F, this year, all went well and I sit about 6-10° above ambient in summer and a consistent 3° above in winter... no icing up issues and only cooler air. Humidity and extreme temperature fluctuations could cause challenges...
     
    Wynnded likes this.
  20. Feb 22, 2025 at 7:51 AM
    #20
    Half Assed

    Half Assed me ne frego

    Joined:
    Jul 6, 2020
    Member:
    #48947
    Messages:
    930
    Heartland Florida
    Vehicle:
    10 crewmax
    The intake and intake manifold are both plastic. I'd bet that bypassing coolant to the throttle body is a negligible difference in power.
     
    HulkSmurf14 likes this.
  21. Feb 22, 2025 at 7:58 AM
    #21
    HulkSmurf14

    HulkSmurf14 ...Weighted Average...

    Joined:
    Aug 9, 2019
    Member:
    #34377
    Messages:
    2,553
    Gender:
    Male
    Vehicle:
    2014 Tundra Limited
    Tastefully enhanced...
    Correct, not enough to feel it, but helps with a more responsive feeling in moving...perhaps...I did it, have no adverse effects while.driving,but can see my IAT are significantly lower with it done...it's just hard to just not do stuff to cars...ha!

    The SABM, however, does provide better breathing, sound, and increases the responsiveness.
     
  22. Feb 24, 2025 at 6:10 AM
    #22
    lr172

    lr172 New Member

    Joined:
    Sep 27, 2024
    Member:
    #123527
    Messages:
    253
    Gender:
    Male
    Vehicle:
    07 DC
    That is a placebo effect. The IAT is measured in the MAF sensor, which is upstream from the TB. In other words, the coolant is warming the air AFTER it has passed the IAT sensor.
     
    HulkSmurf14[QUOTED] and Wynnded like this.
  23. Feb 24, 2025 at 6:35 AM
    #23
    Tundra234

    Tundra234 New Member

    Joined:
    Nov 30, 2018
    Member:
    #22402
    Messages:
    18,055
    Gender:
    Male
    First Name:
    George
    Florida
    Vehicle:
    2020 Tundra DC SR5 Barcelona
    Alot of them
    Let us know how many swear words you create when you install the Stillen. The 2 bolts in the bottom of the box are a PITA!
     
  24. Feb 24, 2025 at 6:54 AM
    #24
    00h2itr

    00h2itr [OP] New Member

    Joined:
    Jan 13, 2025
    Member:
    #128779
    Messages:
    269
    Gender:
    Male
    Carolina's
    Vehicle:
    21 Limited CM TRD-OR
    LOL, should I start a swear word jar before I get going? Then count up the coins in there afterwards?

    I'd read those 2 are a PITA, but the rest looks pretty straightforward. Add in, I'm using the TRD air accelerator, and initially not planning on cutting it or the box, we'll see how that goes :eek2:
     
  25. Feb 24, 2025 at 7:51 AM
    #25
    D60

    D60 New Member

    Joined:
    Feb 6, 2023
    Member:
    #91553
    Messages:
    7
    Gender:
    Male
    Coming from a background of remote 'wheeling and camping, I like dead-simple.

    Coolant is EXTREMELY important and significant leaks are show-stoppers. I guess you can carry sat phones these days, but I'm regularly in places where there is no cell coverage and the average vehicle can't reach me.

    I don't see the point in routing a critical fluid to extraneous locations with small, custom-molded hoses. I'd prefer to reduce the number of hoses and use a straight shot of off-the-shelf hose, or plug the ports altogether if possible.

    But I would never expect "performance" gains. However I judge performance as increased simplicity, reduced risk of breakdown and easier field serviceability.

    And yeah, I imagine these OEM hoses rarely fail. I just don't LIKE KNOWING they're there if they're not necessary. I don't enjoy having the hood up on what should be a relaxing weekend of remote camping.
     
  26. Feb 24, 2025 at 8:31 AM
    #26
    _none_

    _none_ Poser

    Joined:
    Mar 23, 2023
    Member:
    #94306
    Messages:
    459
    Vehicle:
    2020 DC SR5 4x4

    So you're solution is to take something that has a 0% failure rate and modify it to make it less prone to failure? That math ain't mathin'.
     
    D60[QUOTED] and AZBoatHauler like this.
  27. Feb 24, 2025 at 9:01 AM
    #27
    blanchard7684

    blanchard7684 New Member

    Joined:
    Nov 18, 2018
    Member:
    #21856
    Messages:
    906
    Gender:
    Male
    I just want to know what the hell the purpose of this coolant circuit is…
     
  28. Feb 24, 2025 at 9:31 AM
    #28
    _none_

    _none_ Poser

    Joined:
    Mar 23, 2023
    Member:
    #94306
    Messages:
    459
    Vehicle:
    2020 DC SR5 4x4
    Its common, used by many manufacturers. It's to make sure there is no icing/freezing of the throttle body which could lead to the throttle body being stuck partially open.
     
    Rodtheviking and AZBoatHauler like this.
  29. Feb 24, 2025 at 9:36 AM
    #29
    Rodtheviking

    Rodtheviking New Member

    Joined:
    Jan 8, 2021
    Member:
    #57282
    Messages:
    947
    Gender:
    Male
    First Name:
    Chris
    Vancouver, WA
    Vehicle:
    Sequoia
    2015 Sequoia Platinum, Eibach Pro, Bilstein, Tandem Off Road, 12Deg Rock Sliders, RCI, Sherpa Rack
    It defrosts the throttle butterfly valve on REALLY cold start ups. I bypassed the same thing on all my old Land Rovers (bosch throttle body as they all leaked) but there is no performance/intake temp gain.
     
    D60 likes this.
  30. Feb 24, 2025 at 9:57 AM
    #30
    D60

    D60 New Member

    Joined:
    Feb 6, 2023
    Member:
    #91553
    Messages:
    7
    Gender:
    Male
    As mentioned it's supposed to prevent icing on the butterfly. I've never had a problem in CO, but we're pretty arid, even when it's actively snowing.
     

Products Discussed in

To Top