1. Join the Community!

    DSMtuners is a massive archive of DSM information - but more importantly, it's a COMMUNITY! Join in and participate with other DSMers, and invite all of your DSM friends to make this place their home. Chat with others, create a build thread, post questions and answers. Get involved! Logging in will also remove many of the advertisements, along with this notice. ;)

O2 harness wiring

Posted by Rooster, Jun 29, 2020 at 2:38 PM

Please Support Morrison Fabrications
Please Support ExtremePSI
  1. Rooster

    Rooster Proven Member

    45
    5
    Joined Jun 25, 2017
    Somonauk, Illinois
    All these wires are making my head hurt. Can anyone shed some light on how to proceed?
    I was informed by my tuner that the AEM UEGO wideband sensor is junk and messing with the readings for him to be able to tune the car accurately. That being said i was told to revert the wiring of the Wideband to the EGR pin and put the stock o2 harness back together. So i follow the wires from the ECU pin 4 and the UEGO has been spliced into and soldered to the wire for pin 4. Easy enough just cut it out and rewire to EGR.. well then i run into the o2 sensor wiring near the ECU... what am i looking at here and why is there bare wire exposed... this cant be how it comes from the factory. Any way to clean this up so i can get the factory o2 set up properly again?
     

    Attached Files:

    341  6

    1991 Eagle Talon TSi AWD
    awd · automatic · 1G DSM
    Loading...
  2. Vegas smith

    Vegas smith Proven Member

    3,129
    1,673
    Joined Dec 2, 2002
    Houston, Texas
    That’s actually shielding for the wire, I believe, to protect the signal or something. It’s not wire strands. There should only be one signal left to reconnect pin 4.
     

    Street Build 4K  10

    1993 Eagle Talon TSi AWD
    awd · manual · 1G DSM
    Loading...
    TK's9d2TSi and Rooster like this.
  3. Rooster

    Rooster Proven Member

    45
    5
    Joined Jun 25, 2017
    Somonauk, Illinois
    Vegas i might as well pay you for diagnostics at this point. Someone make this guy a wiseman.

    Anyways, youre saying theres something else i need to do to reconnect pin 4 properly? Or if i just cut the white coming from the UEGO ill be all set to rewite to EGR pin?
     

    341  6

    1991 Eagle Talon TSi AWD
    awd · automatic · 1G DSM
    Loading...
  4. TK's9d2TSi

    TK's9d2TSi Supporting Member

    3,075
    1,191
    Joined Sep 11, 2017
    Cincinnati, Ohio
    Correct. Only one wire to that input. If the other end isn’t connected to anything, it doesn’t matter
     

    379  3

    2000 Jeep Cherokee Sport - Classic
    awd · automatic · Misc Vehicles

    409  4

    93 Civic 4 Door -sold-
    fwd · manual · Misc Vehicles

    Street Build 3K  6

    1992 Eagle Talon TSi AWD
    12.2 @ 120 · 1G DSM
    Loading...
  5. Vegas smith

    Vegas smith Proven Member

    3,129
    1,673
    Joined Dec 2, 2002
    Houston, Texas
    If you want your stock narrowband to work then of course you would reconnect that to the o2 pin 4. The o2 has 4 wires, I believe, and I don't remember which one is the signal.
     

    Street Build 4K  10

    1993 Eagle Talon TSi AWD
    awd · manual · 1G DSM
    Loading...
  6. Rooster

    Rooster Proven Member

    45
    5
    Joined Jun 25, 2017
    Somonauk, Illinois
    Sorry for my negligence, i didnt do any of the wiring on this car except trying to fix what the previous owner did. Is there more than one wire that connects to the ecu pin 4? I have 1 white coming out of it. I believe i have it all wired correctly (just finished up wiring it) but i want to make sure i didnt miss anything as im logging in with my tuner again tomorrow and dont want to have to stop because i fked up wiring.

    P.s
    I know each pin has 1 wire coming out, i just didnt know if something was supposed to spliced in or if im missing something.
     

    341  6

    1991 Eagle Talon TSi AWD
    awd · automatic · 1G DSM
    Loading...
  7. Vegas smith

    Vegas smith Proven Member

    3,129
    1,673
    Joined Dec 2, 2002
    Houston, Texas
    You'll almost never have multiple signal wires spliced into anything to my knowledge. So to summarize, move the signal wire coming from wideband (the wire that was connected to pin 4 originally) to egr wire, then reconnect stock o2 signal wire to pin 4. Only one signal wire each time.
     

    Street Build 4K  10

    1993 Eagle Talon TSi AWD
    awd · manual · 1G DSM
    Loading...
  8. Rooster

    Rooster Proven Member

    45
    5
    Joined Jun 25, 2017
    Somonauk, Illinois
    Yeah thats how i have it. They spliced and soldered the signal from the wideband into the pin 4 without cutting the o2 if you follow me. There was 2 wires coming from pin 4, 1 going to front o2 other going to wideband.

    Thanks again vegas!
     

    341  6

    1991 Eagle Talon TSi AWD
    awd · automatic · 1G DSM
    Loading...
  9. Vegas smith

    Vegas smith Proven Member

    3,129
    1,673
    Joined Dec 2, 2002
    Houston, Texas
    That's funny. I remember saying in your other thread there was likely something wrong with the wiring. Haha
    "There must be something wrong with the wideband wiring or it's not setup or installed correctly."
    It's crazy that I've dealt with all this sh** myself so at least now I can help others :)
     

    Street Build 4K  10

    1993 Eagle Talon TSi AWD
    awd · manual · 1G DSM
    Loading...
    Rooster likes this.
  10. Rooster

    Rooster Proven Member

    45
    5
    Joined Jun 25, 2017
    Somonauk, Illinois
    Ik you need to be promoted to wiseman i swear. Who do i talk to about this. appreciate your all your help man.
     

    341  6

    1991 Eagle Talon TSi AWD
    awd · automatic · 1G DSM
    Loading...
  11. JPenny

    JPenny Proven Member

    138
    39
    Joined Feb 24, 2016
    Corpus Christi, Texas
    The bare strands are just shielding from interference noise to the signal wire inside like how rcas or coax cable for TV are. Wiring itself is a nightmare then add 20+ years of age and who knows how many people's hands makes troubleshooting horrible LOL.
    I'm glad Vegas was able to help you hes definitely got some knowledge
     

    157  6

    1996 Mitsubishi Eclipse GST
    manual · 2G DSM

    Street Build 2K  4

    1997 Mitsubishi Eclipse GST
    fwd · manual · 2G DSM
    Loading...
  12. Vegas smith

    Vegas smith Proven Member

    3,129
    1,673
    Joined Dec 2, 2002
    Houston, Texas
    I have no business being considered a wiseman but thank you.
     

    Street Build 4K  10

    1993 Eagle Talon TSi AWD
    awd · manual · 1G DSM
    Loading...

Share This Page

Support Vendors who Support the DSM Community
ECM Tuning ExtremePSI Feal Suspension Fuel Injector Clinic Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications OHM Racing RixRacing RockAuto SouthBay Fuel Injectors STM Tuned Track Decals Track Sculptures VR Speed Factory