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Aem Wideband wiring to rear O2

Posted by v8s_are_slow, Jun 15, 2013

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  1. v8s_are_slow

    v8s_are_slow Proven Member

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    So my car has been down for a year and trying to start it but the O2 sensor isn't heating up. I don't have a stock O2 cause I'm using the Aem to simulate a narrowband. I've tried 2 different Bosch sensors but neither is warming up. Not sure if there's an issue with the wiring so I wanna wire it to where the rear O2 use to be. There's a White wire (Analog output +) and a Brown wire (Analog output -) from the gauge.

    My question...is the black wire for the rear O2 the same wire that goes to pin 92 for the sensor ground? Just want confirmation that I can hookup the White wire to the Red/Yellow wire, and the Brown wire to the Black wire. Thoughts? I can seem to find any threads on how people are running their wiring for the rear O2.

    Oh, and I have a 30-5130 analog gauge just for an fyi.
     

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  2. Archer Fabrications

    Archer Fabrications Proven Member

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    Plug the aem into the pin out for rear o2 and dedicate it in link, that should be all you have to do. I'm simulating also in the front o2 position, using the rear o2 pinout.
     

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    2006 Evo 9 MR
    awd · manual · Lancer Evolution
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  3. v8s_are_slow

    v8s_are_slow Proven Member

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    But do you have both wires going to the rear O2? Or just the white wire, and then splice the brown wire into pin 92 at the ecu? I'm trying to get the wiring away from there.
     

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  4. Archer Fabrications

    Archer Fabrications Proven Member

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    I can look, it's been so long. :/
     

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    2006 Evo 9 MR
    awd · manual · Lancer Evolution
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  5. gofer

    gofer Moderator

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    1997 Mitsubishi Eclipse GST
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  6. v8s_are_slow

    v8s_are_slow Proven Member

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    Thanks for the attempt Gofer, but I'm just talking about using the wiring to the rear O2. Not putting the sensor in the rear location. Lol. But anywho, I pulled the drivers seat out and pulled the wiring that goes to the rear O2 and used that. I didn't wanna wire it in permanently yet because I'm not sure if the sensor is the problem or the gauge itself so I just used a couple of wires with alligator clips to make the connections for now.

    It's running much better but not sure if it's the sensor or the gauge. On Ecmlink, the wideband reading is stuck at 8.5 whereas before I rewired it, it was stuck at 18. Although the gauge still isn't doing crap. The only time it moves is when it's about to die. Then it jumps to like 14 or whatever. Anyway, here's a vid of the wideband and what it's doing.

    [ame=http://www.youtube.com/watch?v=tMEnkG38kjM]Wideband not working - YouTube[/ame]
     

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    1998 Mitsubishi Eclipse GST
    10.949 @ 129.77 · 2G DSM
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  7. Archer Fabrications

    Archer Fabrications Proven Member

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    I didn't use any of the rear o2's existing wiring. I chopped it off actually. Everything from the gauge went straight to power and the ecu pin out where the rear o2 was pinned in, can't say colors of wires sorry.
     

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    2006 Evo 9 MR
    awd · manual · Lancer Evolution
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  8. gofer

    gofer Moderator

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    Guess I'm still not sure what you're trying to do but from what I can tell you're having a hard time determining if the issue (you're describing) is the gauge or the sensor causing it.

    Unplug the sensor harness from the back of the gauge, its the smaller of the two connectors, and if the gauge is working properly it will display a 14.7:1 AFR.

    That should get you halfway there, what does the WBRawVoltage look like in the log?

    :dsm:
     

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  9. MY1GDSM

    MY1GDSM Proven Member

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    EDIT: LINK ABOVE IN POST 5 IS NOT FOR THIS GAUGE... .


    As well if you have issues with the wideband not reading the same in Link take a Look Here.
     
    Last edited: Jun 15, 2013

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  10. Archer Fabrications

    Archer Fabrications Proven Member

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    I curious what if my wb says 14.8 when sensor is unplugged. Wonder if my sensor is .1 off from the factory. :hmm:
     

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    awd · manual · Lancer Evolution
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  11. MY1GDSM

    MY1GDSM Proven Member

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    You would just use that as your reference point... 14.7 and 14.8 are VERY close to the same voltage. About half the gauges do that... Being you can't calibrate the sensor from the way it ships for the factory... I'll leave that to everyone else to decide.

    Really I can't believe that anyone runs these damn things anymore still. There are SO many posted telling people about the ground offsets they tend to have as well as how they don't play nice with all the Inputs for our Ecu's. Not to mention if the Sensor for example is having an issue with Overheating say in the Front o2 the the AEM is clueless and won't tell you. At least a Lc-1 or Mtx-l or something else Innovate Will give you an error code and let you know. A AEM well just cross your fingers is you have an issue as it will likely just report a wrong AFR rather.

    And to top it off

    LOOK AT THIS HERE

    I'd have to look around for another one of these that explains how much More of a difference the AEM has in latency compared to about any other Wideband on the Market. It's something like 24 or 64 combustion events that is misses before updating vs the competitors. Anyone who doubts this just pull some logs for the forums here and compare a log with a AEM vs anything else and it will be plain as day.

    Sorry OP
    /Rant
     

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    1991 Eagle Talon TSi AWD
    manual · 1G DSM
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  12. v8s_are_slow

    v8s_are_slow Proven Member

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    So I went out and turned on the ignition, with the sensor out but it stayed at 8.5 and after plugging it in, it stayed at 8.5 as well. Nothing changed. The Raw voltage was 0.04. Hoping I attached the log correctly.

    Anyway, posting a video cause I figure videos are easier for people to understand what I'm doing. And not sure if unplugging the wideband applies to mine. It's not a digital gauge. And it has lights that flash if there's an error....which it's doing. If I unplug the small plug, it turns off the gauge. If I unplug the big plug and plug it back in, it goes to 14.5 for a second (you don't see that part in the video), then back to 18. Sorry if the vid sucks. Also, I think I said pin 2, but meant pin 92. Oops.

    [ame=http://www.youtube.com/watch?v=O_3GX7H7K_k]Aem wiring and issues - YouTube[/ame]
     

    Attached Files:

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    1998 Mitsubishi Eclipse GST
    10.949 @ 129.77 · 2G DSM
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  13. MY1GDSM

    MY1GDSM Proven Member

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    Oh that gauge... .It doesn't default to 14.7... . Also Corey was saying to disconnect the Sensor from the harness not the gauge. It shouldn't matter too much on most. But not everything has the same wiring as you will see in the Instructions. So it's best to do it that way... .

    Take a look at the instructions. HERE as it's a bit differant then others. Take note the you need the brown wire hood up to a 5v sensor ground.

    The Gauge in the video is flashing a code because you have no sensor hooked up. If it is still flashing when it's hooked up. Reference there "wonderful" Glossary for codes.

    Whether you want to or not. You shouldn't be hooking things up back there under the seat.

    If you don't want to cut the harness. Pull the pin from the harness and replace it with another spare ran to the white wire as short as possible.

    EDIT: Just took a look at the first Video it looks like right when you ended the vid that the sensor finally warmed up as it blinks for when it's warming up as well as if you have a non descriptive problem. Most take a good 30 seconds to start reading/warming up.
     

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    1991 Eagle Talon TSi AWD
    manual · 1G DSM
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  14. v8s_are_slow

    v8s_are_slow Proven Member

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    Okay first, why wouldn't I wanna hook it up under the seat? I mean when I figure out the problem, I plan to solder it and use heat shrink and run it under the carpet.

    I've looked at the directions and the flashes and all but when I had it hooked up at the ecu, it'd just flash non-stop. Now that I have it hooked up this way, it at least gives me 5 flashes and runs much better than it did.

    Not sure what wire you're talking about cutting or what pin you're talking about pulling, etc. As for the video, it goes to 14.5 for a second, then back to 18. It doesn't stay at 14.5. Aggravated....
     

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    1998 Mitsubishi Eclipse GST
    10.949 @ 129.77 · 2G DSM
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  15. MY1GDSM

    MY1GDSM Proven Member

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    Because it could be very well part of the issue.
    You are logging an Analog signal on a Sub par (IMO) Wideband... . Would you would rather the signal travel over a few inches of wire or more than several feet?

    Not sure what else to say... If the gauge is going in the car do it once and do it right.

    Where are you getting your power source from where is the Brown wire tapped in? FYI
    I was editing my post when you quoted me.(which I have the post above so ya... .)
     

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    1991 Eagle Talon TSi AWD
    manual · 1G DSM
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  16. v8s_are_slow

    v8s_are_slow Proven Member

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    I gotcha now. Just didn't know what you were getting at. I just don't trust splice connectors though and don't wanna hack the wiring at the ecu.

    As for the wiring, right now the brown wire is going to black wire under the seat, and white wire going to the red/yellow wire under the seat. The red and pink wires are going to appropriate fuses at the fuse panel under the dash. Black wires going to a chassis ground close to the fuse panel.

    Aside from that, I still can't tell if it's the gauge, sensor, or wiring. Nothing changed in the car other than just putting in another motor. Wondering if a local parts store would have a Bosch sensor and which part number to look for.

    Still wondering what wire you're talking about cutting.
     

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    1998 Mitsubishi Eclipse GST
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  17. MY1GDSM

    MY1GDSM Proven Member

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    Plain and simple... .

    Pin 75 at the ECU needs cut and feed the signal It's one wire that will probably never go to the rear o2 again anyway as long as you have an EMS of some sort ... You need a good 5v Sensor Ground as well. All this should be done with as little as possible wire soldered and as close to the ECU wiring as you can get... . Doing things the way you are I don't see you resolving any issues or diagnosing them for that matter.
     

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  18. v8s_are_slow

    v8s_are_slow Proven Member

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    Guess I'll do this as soon as possible and post back the results. But just to be clear, cut the wire, and solder the white wire to the end of the wire that's left and going to the ecu, and the other side of that wire that's on the harness side, just leave hanging.....correct???
     

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    1998 Mitsubishi Eclipse GST
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  19. MY1GDSM

    MY1GDSM Proven Member

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    Yes, that is correct.
     

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  20. v8s_are_slow

    v8s_are_slow Proven Member

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    All wired up properly and soldered. Log also posted with sensor connected and disconnected. Notice it stays at 8.5 regardless.

    [ame=http://www.youtube.com/watch?v=ocepH7Jpp4o]June 15, 2013 10:32 PM - YouTube[/ame]

    Not seeing any way to test just the gauge itself so decided to bite the bullet and buy a new sensor. Should have it Tuesday so hopefully I'll have good results.
     

    Attached Files:

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    1998 Mitsubishi Eclipse GST
    10.949 @ 129.77 · 2G DSM
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  21. v8s_are_slow

    v8s_are_slow Proven Member

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    Ordered the new sensor and the wrong one came yesterday so ordered another and got it today. Installed and still not working correctly. So I said screw it and called up AEM tech support. They said it's my O2 sensor harness. So I yanked the entire harness and checked for continuity for each wire and all checked out. And while probing one wire, I even checked to make sure the other wires weren't maybe rubbing together and touching. That checked out good as well.

    About ready to throw this dang wideband in the garbage. Just wish I had money for another wideband. Might be awhile before I have any extra cash :(

    I feel...:barf:
     

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  22. gofer

    gofer Moderator

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    This is what everyone should do if they own a AEM WB, working or not because they NEVER work even from the box when you're talking about how accurate they log in Link.

    Sorry to hear you dropped $60 on a new sensor. Personally, I'd say sell the sensor here and eat a few dollars doing it. Then put that money towards a used LC1 or MTXL and never look back, a failing AEM WB is a GOOD thing. Maybe not financially but for your car and tuning, it's a good thing.

    Email the tech from AEM and tell them the harness has continuity pin to pin and, if it's that important to you, see if you can't mail them the gauge/wiring and ask if they can't find they can't find the problem. Then order the LC1/MTXL even if they do. LOL

    :dsm:
     

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  23. v8s_are_slow

    v8s_are_slow Proven Member

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    Starting to wonder if I'm having an issue with the ecu. But I wanna make sure before I throw anymore money to guess at a problem. I don't have the money to screw around right now. Annoyed though, that's for sure.
     

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  24. gofer

    gofer Moderator

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    Well, I just checked your log and I see a HUGE issue there. Probably not going to fix your gauge but, potentially because it's getting voltage feedback maybe?

    In your log you're pin assignment for the WB is on the front o2 sensor but, for the ECU side, you're using the rear o2 sensor for narrowband sim. You need to figure out what wire you're logging across on the ECU, pin 75 is the rear o2 and pin 76 is the front o2. They're both white wires and they are right next to each other so they're very easily confused...

    Once you figure out which one you're using to log make sure its CUT, not taped, and the ECU harness side of the wire is connected to the gauge. Then make sure your ECMLink settings reflect that because right now they're showing you've got the WB on two different inputs.

    WB settings.jpg

    :dsm:
     
    Last edited by a moderator: Jul 10, 2014

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  25. v8s_are_slow

    v8s_are_slow Proven Member

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    Crap, I didn't even notice that. Thanks! Gonna make the changes and then try it out but it's a little late tonight to fire up my car with a side exit exhaust....and in the garage. My woman would wake up and kill me. Lol.

    Maybe my sensor WAS bad, but I was a douche and didn't change the settings like I should've. Sigh....guess we'll see. Thanks for noticing and bringing it to my attention.

    Made the changes but still no worky. However the wideband readings and the gauge match now. Was gonna check the voltage at pin 75 and 92, but my multimeter died on me. Oh well. Also, O2 sensor gets a little warm, but not hot. New log posted.
     

    Attached Files:

    Last edited: Jun 20, 2013

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    1998 Mitsubishi Eclipse GST
    10.949 @ 129.77 · 2G DSM
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