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
    Quick Links: O2 Sensors don't match? Temperature gauge sits high but temps are normal Sound systems for your Tacoma After market 3rd brake light Gear oil for rearend? [A340F Question] Little Bonk Between 1st & Neutral

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

    #1
    Actionjackson [OP] Well-Known Member

    Joined:
    Aug 21, 2014
    Member:
    #136623
    Messages:
    383
    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.
     
    Actionjackson, Jan 12, 2018
    #1
  2. Jan 12, 2018 at 1:54 PM
    #2
    Speedytech7

    #2
    Speedytech7 Toyota Cult Ombudsman

    Joined:
    Feb 20, 2014
    Member:
    #123587
    Messages:
    52,598
    Gender:
    Male
    First Name:
    ゼイン
    5520 E Sprague Ave, Spokane Valley, WA 99212
    Vehicle:
    93 80 Series LC & 96 Turbo V6 Taco 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?
     
    Speedytech7, Jan 12, 2018
    #2
  3. Jan 12, 2018 at 3:53 PM
    #3
    Actionjackson

    #3
    Actionjackson [OP] Well-Known Member

    Joined:
    Aug 21, 2014
    Member:
    #136623
    Messages:
    383
    Gender:
    Male
    First Name:
    Jack
    MA
    Vehicle:
    2004 Tacoma
    Actionjackson, Jan 12, 2018
    #3
  4. Jan 12, 2018 at 3:56 PM
    #4
    Speedytech7

    #4
    Speedytech7 Toyota Cult Ombudsman

    Joined:
    Feb 20, 2014
    Member:
    #123587
    Messages:
    52,598
    Gender:
    Male
    First Name:
    ゼイン
    5520 E Sprague Ave, Spokane Valley, WA 99212
    Vehicle:
    93 80 Series LC & 96 Turbo V6 Taco 4WD
    I've done a mod or two
    Speedytech7, Jan 12, 2018
    #4
  5. Jan 12, 2018 at 4:01 PM
    #5
    ghs57

    #5
    ghs57 Well-Known Member

    Joined:
    Jul 27, 2010
    Member:
    #40832
    Messages:
    1,091
    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:

    ghs57, Jan 12, 2018
    #5
    Speedytech7 likes this.
  6. Jan 12, 2018 at 4:09 PM
    #6
    ghs57

    #6
    ghs57 Well-Known Member

    Joined:
    Jul 27, 2010
    Member:
    #40832
    Messages:
    1,091
    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.
     
    ghs57, Jan 12, 2018
    #6
  7. Jan 12, 2018 at 4:30 PM
    #7
    2stroketrush

    #7
    2stroketrush Well-Known Member

    Joined:
    Feb 4, 2012
    Member:
    #72157
    Messages:
    1,166
    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.
     
    2stroketrush, Jan 12, 2018
    #7
  8. Jan 12, 2018 at 4:38 PM
    #8
    ghs57

    #8
    ghs57 Well-Known Member

    Joined:
    Jul 27, 2010
    Member:
    #40832
    Messages:
    1,091
    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.
     
    ghs57, Jan 12, 2018
    #8
  9. Jan 16, 2018 at 7:08 PM
    #9
    Actionjackson

    #9
    Actionjackson [OP] Well-Known Member

    Joined:
    Aug 21, 2014
    Member:
    #136623
    Messages:
    383
    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.
     
    Actionjackson, Jan 16, 2018
    #9
  10. Jan 16, 2018 at 7:08 PM
    #10
    Actionjackson

    #10
    Actionjackson [OP] Well-Known Member

    Joined:
    Aug 21, 2014
    Member:
    #136623
    Messages:
    383
    Gender:
    Male
    First Name:
    Jack
    MA
    Vehicle:
    2004 Tacoma
    Man do i got fat fingers.....
     
    Actionjackson, Jan 16, 2018
    #10
    eon_blue likes this.

Products Discussed in

Denso 234-4189 Oxygen Sensor
$60.51
Denso 234-9003 Air Fuel Ratio Sensor
$169.99
To Top