1. Welcome to Tacoma World!

    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 Tacoma discussion topics
    • Communicate privately with other Tacoma owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

CEL is on

Discussion in '1st Gen. Tacomas (1995-2004)' started by DaytonLax14, Sep 20, 2010.

  1. Sep 20, 2010 at 3:51 PM
    #1
    DaytonLax14

    DaytonLax14 [OP] Well-Known Member

    Joined:
    Nov 6, 2009
    Member:
    #25531
    Messages:
    502
    Gender:
    Male
    First Name:
    Corey
    Ohio
    Vehicle:
    98 extended cab TRD Off Road
    PO #136 o2 sensor, PO #125 Bank 1 sensor 2, PO 136 insufficient cooling temp for closed loop fuel control.



    Anyone know how much this is going to cost me?
     
  2. Sep 20, 2010 at 4:01 PM
    #2
    98tacoma27

    98tacoma27 is gooder 'en chicken Moderator

    Joined:
    Dec 18, 2008
    Member:
    #11714
    Messages:
    49,839
    Gender:
    Male
    First Name:
    Ben
    Beech Creek
    Vehicle:
    05 Tundra SR5 (+250k AND COUNTING), 88 SR5 PU (SOLD), 98 TRD OR (CRUSHED)
    5100's all on fours
    $68 at www.rockauto.com for the sensor DENSO Part # 2344162

    $20-40 for the coolant sensor also.

    Chcek the vendor section to see if Rockauto still has a valid member discount.
     
  3. Sep 20, 2010 at 4:46 PM
    #3
    DaytonLax14

    DaytonLax14 [OP] Well-Known Member

    Joined:
    Nov 6, 2009
    Member:
    #25531
    Messages:
    502
    Gender:
    Male
    First Name:
    Corey
    Ohio
    Vehicle:
    98 extended cab TRD Off Road
    what about the 3rd thing that's wrong with it?
     
  4. Sep 20, 2010 at 4:47 PM
    #4
    98tacoma27

    98tacoma27 is gooder 'en chicken Moderator

    Joined:
    Dec 18, 2008
    Member:
    #11714
    Messages:
    49,839
    Gender:
    Male
    First Name:
    Ben
    Beech Creek
    Vehicle:
    05 Tundra SR5 (+250k AND COUNTING), 88 SR5 PU (SOLD), 98 TRD OR (CRUSHED)
    5100's all on fours
    You only have two listed.
     
  5. Sep 20, 2010 at 5:06 PM
    #5
    DaytonLax14

    DaytonLax14 [OP] Well-Known Member

    Joined:
    Nov 6, 2009
    Member:
    #25531
    Messages:
    502
    Gender:
    Male
    First Name:
    Corey
    Ohio
    Vehicle:
    98 extended cab TRD Off Road
    I posted 3 different numbers though
     
  6. Sep 20, 2010 at 5:08 PM
    #6
    98tacoma27

    98tacoma27 is gooder 'en chicken Moderator

    Joined:
    Dec 18, 2008
    Member:
    #11714
    Messages:
    49,839
    Gender:
    Male
    First Name:
    Ben
    Beech Creek
    Vehicle:
    05 Tundra SR5 (+250k AND COUNTING), 88 SR5 PU (SOLD), 98 TRD OR (CRUSHED)
    5100's all on fours
    I only see two. 136 (twice) and 125
     
  7. Sep 20, 2010 at 5:12 PM
    #7
    DaytonLax14

    DaytonLax14 [OP] Well-Known Member

    Joined:
    Nov 6, 2009
    Member:
    #25531
    Messages:
    502
    Gender:
    Male
    First Name:
    Corey
    Ohio
    Vehicle:
    98 extended cab TRD Off Road
    oh okay i see my bad. so the second time it says 136 it's just telling me what it's for?

    are these things that i can do myself?
     
  8. Sep 20, 2010 at 5:16 PM
    #8
    98tacoma27

    98tacoma27 is gooder 'en chicken Moderator

    Joined:
    Dec 18, 2008
    Member:
    #11714
    Messages:
    49,839
    Gender:
    Male
    First Name:
    Ben
    Beech Creek
    Vehicle:
    05 Tundra SR5 (+250k AND COUNTING), 88 SR5 PU (SOLD), 98 TRD OR (CRUSHED)
    5100's all on fours
    You have one 136 active and probably one pending. Yes, they are easy to do. The rear O2 is easy to access (136). The 125 is the coolant temp sensor. It should be located by the thermostat IIRC. It just unscrews out. Use teflon tape on the threads before you install the new one.
     
  9. Sep 26, 2010 at 11:42 AM
    #9
    DaytonLax14

    DaytonLax14 [OP] Well-Known Member

    Joined:
    Nov 6, 2009
    Member:
    #25531
    Messages:
    502
    Gender:
    Male
    First Name:
    Corey
    Ohio
    Vehicle:
    98 extended cab TRD Off Road
    do you know if i need an upstream or downstream o2 sensor?
     
  10. Sep 26, 2010 at 12:29 PM
    #10
    DocBrown86

    DocBrown86 Yota Doc

    Joined:
    May 16, 2010
    Member:
    #37266
    Messages:
    107
    Gender:
    Male
    First Name:
    Brian
    San Diego (Spring Valley)
    Vehicle:
    04 Prerunner
    toytec coil spacers, tokicko struts/dubcab springs, energy suspension rack bushings, bilstien hd shocks, K&N FIPK2, Flowmaster 50DF, ScanGuage2, 5000k HID's, horn mod, other stuff that I forgot to list
    I'd change the coolant temp sensor first. It may be throwing the O2 sensor code.

    Change the coolant temp sensor, drive the truck around, and make sure the CEL dosent come back.

    EDIT


    Toyota has a variation on P0125. The generic meaning is insufficient engine coolant temp.

    But Toyotas definition is "open or short in heated 02 sensor (bank 1 sensor 1) circuit"

    So these codes have nothing to do with your engine coolant temp.

    PS- Is there a third code that you meant to list but didnt?
     
  11. Sep 26, 2010 at 12:48 PM
    #11
    DocBrown86

    DocBrown86 Yota Doc

    Joined:
    May 16, 2010
    Member:
    #37266
    Messages:
    107
    Gender:
    Male
    First Name:
    Brian
    San Diego (Spring Valley)
    Vehicle:
    04 Prerunner
    toytec coil spacers, tokicko struts/dubcab springs, energy suspension rack bushings, bilstien hd shocks, K&N FIPK2, Flowmaster 50DF, ScanGuage2, 5000k HID's, horn mod, other stuff that I forgot to list
    P0125- upstream
    p0136- downstream

    You will also need an 02 sensor socket.
     
  12. Sep 26, 2010 at 3:41 PM
    #12
    DaytonLax14

    DaytonLax14 [OP] Well-Known Member

    Joined:
    Nov 6, 2009
    Member:
    #25531
    Messages:
    502
    Gender:
    Male
    First Name:
    Corey
    Ohio
    Vehicle:
    98 extended cab TRD Off Road
    Okay I got the coolant temperature sensor so I'll put that in and drive around and see if the light doesn't come back on.
     
  13. Sep 26, 2010 at 3:51 PM
    #13
    DaytonLax14

    DaytonLax14 [OP] Well-Known Member

    Joined:
    Nov 6, 2009
    Member:
    #25531
    Messages:
    502
    Gender:
    Male
    First Name:
    Corey
    Ohio
    Vehicle:
    98 extended cab TRD Off Road
    Could someone explain where the sensor is supposed to go? I found the thermostat but I can't seem to find the sensor
     
  14. Sep 27, 2010 at 12:51 AM
    #14
    DocBrown86

    DocBrown86 Yota Doc

    Joined:
    May 16, 2010
    Member:
    #37266
    Messages:
    107
    Gender:
    Male
    First Name:
    Brian
    San Diego (Spring Valley)
    Vehicle:
    04 Prerunner
    toytec coil spacers, tokicko struts/dubcab springs, energy suspension rack bushings, bilstien hd shocks, K&N FIPK2, Flowmaster 50DF, ScanGuage2, 5000k HID's, horn mod, other stuff that I forgot to list
    The coolant temp sensor is near your upper radiator hose, under the fuel rail.

    However, the code you listed was not for your coolant temp sensor. It's for your upstream oxygen sensor.

    p0125 (generic obd2) = Coolant temp sensor.
    p0125 (Toyota specific obd2) = Upstream o2 sensor.
     
  15. Sep 27, 2010 at 4:44 AM
    #15
    98tacoma27

    98tacoma27 is gooder 'en chicken Moderator

    Joined:
    Dec 18, 2008
    Member:
    #11714
    Messages:
    49,839
    Gender:
    Male
    First Name:
    Ben
    Beech Creek
    Vehicle:
    05 Tundra SR5 (+250k AND COUNTING), 88 SR5 PU (SOLD), 98 TRD OR (CRUSHED)
    5100's all on fours
  16. Sep 27, 2010 at 8:25 AM
    #16
    biggdog747

    biggdog747 Well-Known Member

    Joined:
    Mar 7, 2010
    Member:
    #32729
    Messages:
    57
    Gender:
    Male
    MI
    Vehicle:
    taco
    P0125 Insufficient Coolant Temp. For Closed Loop put a t-stat and coolant in it not a coolant temp sensor. what that is telling you is that the t-stat didnt open all the way one or more times for closed loop. every time we get that code we put that in it and its all good. toyota coolant temp sensors dont go bad that often.
     
  17. Sep 27, 2010 at 8:59 AM
    #17
    DaytonLax14

    DaytonLax14 [OP] Well-Known Member

    Joined:
    Nov 6, 2009
    Member:
    #25531
    Messages:
    502
    Gender:
    Male
    First Name:
    Corey
    Ohio
    Vehicle:
    98 extended cab TRD Off Road
    it's got plenty of coolant in it (the overflow tank is about 1/4 full), but what is t stat?
     
  18. Sep 27, 2010 at 9:03 AM
    #18
    98tacoma27

    98tacoma27 is gooder 'en chicken Moderator

    Joined:
    Dec 18, 2008
    Member:
    #11714
    Messages:
    49,839
    Gender:
    Male
    First Name:
    Ben
    Beech Creek
    Vehicle:
    05 Tundra SR5 (+250k AND COUNTING), 88 SR5 PU (SOLD), 98 TRD OR (CRUSHED)
    5100's all on fours
    thermostat
     
  19. Sep 27, 2010 at 9:04 AM
    #19
    DaytonLax14

    DaytonLax14 [OP] Well-Known Member

    Joined:
    Nov 6, 2009
    Member:
    #25531
    Messages:
    502
    Gender:
    Male
    First Name:
    Corey
    Ohio
    Vehicle:
    98 extended cab TRD Off Road
    okay let's back up a bit here because i'm a bit confused:(


    What needs replaced?
     
  20. Sep 27, 2010 at 9:11 AM
    #20
    98tacoma27

    98tacoma27 is gooder 'en chicken Moderator

    Joined:
    Dec 18, 2008
    Member:
    #11714
    Messages:
    49,839
    Gender:
    Male
    First Name:
    Ben
    Beech Creek
    Vehicle:
    05 Tundra SR5 (+250k AND COUNTING), 88 SR5 PU (SOLD), 98 TRD OR (CRUSHED)
    5100's all on fours
    Before you just go throw money at parts, do this.

    Take the thermostat out. It should be closed. Place it in boiling water and it should open. If neither of these turns out true, then replace the thermostat. It's like an $8 part last time I got one.

    Then check the ECT sensor using this. If it tests negative, then replace it too.
     
To Top