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

Do I need new cats?

Discussion in '1st Gen. Tacomas (1995-2004)' started by Actionjackson, Jan 12, 2018.

  1. Jan 12, 2018 at 1:30 PM
    #1
    Actionjackson

    Actionjackson [OP] Well-Known Member

    Joined:
    Aug 21, 2014
    Member:
    #136623
    Messages:
    276
    Gender:
    Male
    First Name:
    Jack
    MA
    Vehicle:
    2004 Tacoma
    Howdy 2004 TRD V6. Just installed denso dnstream 02 sensor to eliminate p0136 cel. Just came back on. Ordered new denso upstream. If that don' fix it, how can I tell if my cats are bad? And which one? Truck runs/ starts great. No other symptoms. Rarely get small evap leak cel but vsv valves check out And I can' find any cracked hoses. Thanks to all who reply.
     
  2. Jan 12, 2018 at 1:54 PM
    #2
    Speedytech7

    Speedytech7 Toyota Cult Ombudsman

    Joined:
    Feb 20, 2014
    Member:
    #123587
    Messages:
    29,297
    Gender:
    Male
    First Name:
    Zane
    Spokane, WA
    Vehicle:
    93 Land Cruiser & 96 Tacoma V6 4WD
    I've done a mod or two
    Did it come back as a P0136? That is o2 voltage low which would indicate a o2 sensor or wiring issue or some sort of magic extremely good cat. Cat usually leads to a P0420 code instead indicating high voltage or poor cat performance. You 100% sure you got the right replacement sensor?
     
  3. Jan 12, 2018 at 3:53 PM
    #3
    Actionjackson

    Actionjackson [OP] Well-Known Member

    Joined:
    Aug 21, 2014
    Member:
    #136623
    Messages:
    276
    Gender:
    Male
    First Name:
    Jack
    MA
    Vehicle:
    2004 Tacoma
  4. Jan 12, 2018 at 3:56 PM
    #4
    Speedytech7

    Speedytech7 Toyota Cult Ombudsman

    Joined:
    Feb 20, 2014
    Member:
    #123587
    Messages:
    29,297
    Gender:
    Male
    First Name:
    Zane
    Spokane, WA
    Vehicle:
    93 Land Cruiser & 96 Tacoma V6 4WD
    I've done a mod or two
  5. Jan 12, 2018 at 4:01 PM
    #5
    ghs57

    ghs57 Well-Known Member

    Joined:
    Jul 27, 2010
    Member:
    #40832
    Messages:
    1,089
    Gender:
    Male
    First Name:
    Chops
    Catskill Mts. NY
    Vehicle:
    '07 Black TRD OR xtracab 4.0L 4WD
    Pretty much stock right now
    P0136 is not necessarily cat related, but sensor related. Check the FSM for that code attached below.
     

    Attached Files:

    Speedytech7 likes this.
  6. Jan 12, 2018 at 4:09 PM
    #6
    ghs57

    ghs57 Well-Known Member

    Joined:
    Jul 27, 2010
    Member:
    #40832
    Messages:
    1,089
    Gender:
    Male
    First Name:
    Chops
    Catskill Mts. NY
    Vehicle:
    '07 Black TRD OR xtracab 4.0L 4WD
    Pretty much stock right now
    Yeah, upstream also. Changing it may solve the problem.

    I had this code a while back. Changed the sensor. Still had the code, and no other codes. Did the diagnostics, and everything checked out. Checked the wiring and connections, including the relay. Maybe reconnecting the plugs and relay fixed a bad connection because that code did not come back, but I got new ones for EVAP leaks. Has a bad VSV, and it's been good ever since.
     
  7. Jan 12, 2018 at 4:30 PM
    #7
    2stroketrush

    2stroketrush Well-Known Member

    Joined:
    Feb 4, 2012
    Member:
    #72157
    Messages:
    1,168
    Gender:
    Male
    First Name:
    Tyler Addison Rush
    Baltimore
    Vehicle:
    Built 97 ExtraCab
    Overland Purpose Built 97 going on 190K.
    drive her hard for 10 minutes, then get out an look to see if the CAT is glowing red ( from heat ) if so its more then likely faulty.
     
  8. Jan 12, 2018 at 4:38 PM
    #8
    ghs57

    ghs57 Well-Known Member

    Joined:
    Jul 27, 2010
    Member:
    #40832
    Messages:
    1,089
    Gender:
    Male
    First Name:
    Chops
    Catskill Mts. NY
    Vehicle:
    '07 Black TRD OR xtracab 4.0L 4WD
    Pretty much stock right now
    I don't think that necessary in this case. The computer will throw a DTC when the cat efficiency drops below the minimum. Even then, there may be another cause. I had a low efficiency code, and it turned out to be a leaky gasket ahead of the downstream sensor. I'm still running the original cats.
     
  9. Jan 16, 2018 at 7:08 PM
    #9
    Actionjackson

    Actionjackson [OP] Well-Known Member

    Joined:
    Aug 21, 2014
    Member:
    #136623
    Messages:
    276
    Gender:
    Male
    First Name:
    Jack
    MA
    Vehicle:
    2004 Tacoma
    Got the sensor and wideband in the right locatioms. Still got cel. Turned out tobe the gasket was not sealing because the stud threads are crappy and the nuts ( ne w ones caust the old ones rusted out) tightened up before the gasket was squeezed enough to seal. Some washers inder the nuts solved it. Mo cel so far. BIG THANKS TO ALL.
     
  10. Jan 16, 2018 at 7:08 PM
    #10
    Actionjackson

    Actionjackson [OP] Well-Known Member

    Joined:
    Aug 21, 2014
    Member:
    #136623
    Messages:
    276
    Gender:
    Male
    First Name:
    Jack
    MA
    Vehicle:
    2004 Tacoma
    Man do i got fat fingers.....
     
    eon_blue likes this.

Products Discussed in

To Top