The Official Jeep Wrangler TJ Oxygen (O2) Sensor Thread

I finally got the O2 sensors, all four of them that mentioned in here.

and I faced a problem!
one of the sensors in my TJ was ripped off of the wire connector.

What I see now is the following:
1- Sensor connected to the exhaust
2- No wiring on it
3- The wire with connector that connects to it has no connector and just a spaghetti wire.

So, I can replace 3 but the fourth I guess I cannot since there is no connector that can be connected to it.


My question is:
Will there be a problem if I just took off all the sensors (all 4 oxygen sensors) and not connect them at all?



I ordered the OBDII scanner that you once recommended:
https://www.amazon.com/dp/B077F8F6TB/?tag=wranglerorg-20

When I connected it, it didn't work no light at all.
Plus, I connected another one and it didn't connect either.

Any suggestions?

You can't drive your TJ with no O2 sensors, it won't run right.

Technically you can get rid of the post cat O2 sensors (but you would need HP Tuners to disable the check engine light from this), but you have to keep the pre-cat O2 sensors, as they give feedback to the PCM and affect how the engine runs.

As for the OBDII scanner not working, maybe it's defective. You plug it in, turn the ignition to the on position (but don't start the vehicle), and it should turn the scanner on.
 
You can't drive your TJ with no O2 sensors, it won't run right.

Technically you can get rid of the post cat O2 sensors (but you would need HP Tuners to disable the check engine light from this), but you have to keep the pre-cat O2 sensors, as they give feedback to the PCM and affect how the engine runs.

As for the OBDII scanner not working, maybe it's defective. You plug it in, turn the ignition to the on position (but don't start the vehicle), and it should turn the scanner on.

That would be bad then, I won't be able to change the sensors since one of them won't be changed as there is not connector cable for it to the engine.

Regarding OBDII scanner yes I tried that, no luck.
Attach files
Could it be from the TJ?
like the clip that you attack the scanner to it, won't be working?
 
That would be bad then, I won't be able to change the sensors since one of them won't be changed as there is not connector cable for it to the engine.

Regarding OBDII scanner yes I tried that, no luck.
Attach files
Could it be from the TJ?
like the clip that you attack the scanner to it, won't be working?

Yes, there’s a chance your OBDII port isn’t working. It would be best to find someone with another OBDII scanner and plug it in to see if it works. If both of them don’t work, your port is having issues.
 
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Are you saying that there is no wiring harness with connector to connect the new O2 sensor connector to?

Are there just wires, as if the wire harness side connector was ripped of or removed? Is so, you might be able to get a new wire harness side connector and crimp it on.
 
I’ve thrown CEL P0138 twice the past week and it’s cleared itself after a day or two. I have all 4 02 sensors from this thread on order.

She is running good at speed but can be rough at idle. The rough idle comes and goes and isn’t consistent but is worse since it’s started throwing the CEL. There have been a couple times at start up in the past where it starts rough but smoothes out after a few seconds. Anything else I should be checking or preemptively order and replace? 2004 LJ with 110,000 miles.
 
I’ve thrown CEL P0138 twice the past week and it’s cleared itself after a day or two. I have all 4 02 sensors from this thread on order.

She is running good at speed but can be rough at idle. The rough idle comes and goes and isn’t consistent but is worse since it’s started throwing the CEL. There have been a couple times at start up in the past where it starts rough but smoothes out after a few seconds. Anything else I should be checking or preemptively order and replace? 2004 LJ with 110,000 miles.

At 110k miles and 15 years old, there's a chance the cats could be on their way out as well. I wouldn't jump to that conclusion yet, but I'm just saying it is technically possible.
 
Chris, I am new to the forum, read your article and used it to replace bank 1 sensor 2 today on the tj, thanks and have a great Thanksgiving, looking forward to the future with the forum, thanks again
 
Hey all! I have a 2005 Wrangler. The clip on bank 2 sensor 2 melted together. Where this clip is I can't get my hands in with a wire crimper to splice a new clip to the side that runs to the computer side. I also can't figure out which cluster of wires this is that runs to the computer side to pull out from the back of the engine. The only wiring schematics I can find only show the O2 sensor up to the clip and where it plugs into the exhaust. I need the rest of it, after the clip. Anyone have these wiring schematics available so I can rewire the thing? Or where I can get them? Or a better idea of how to get a new clip spliced in?
 
Which is the preferred 02 socket type, regular deep well with a notch cut out or the offset style?

Also, I have an '04 with an '03 Cherokee engine. How can I tell which PCM I have?
 
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Hey all! I have a 2005 Wrangler. The clip on bank 2 sensor 2 melted together. Where this clip is I can't get my hands in with a wire crimper to splice a new clip to the side that runs to the computer side. I also can't figure out which cluster of wires this is that runs to the computer side to pull out from the back of the engine. The only wiring schematics I can find only show the O2 sensor up to the clip and where it plugs into the exhaust. I need the rest of it, after the clip. Anyone have these wiring schematics available so I can rewire the thing? Or where I can get them? Or a better idea of how to get a new clip spliced in?

Download a free copy of the FSM here:
Jeep Wrangler TJ Factory Service Manuals (FSM) & Technical Documentation

It's got all the wiring schematics and diagrams in it.
 
Which is the preferred 02 socket type, regular deep well with a notch cut out or the offset style?

Also, I have an '04 with an '03 Cherokee engine. How can I tell which PCM I have?

If I remember correctly, I used one with a notch cut out.

As for the PCM, you can read get the part number off of it. It's usually on a sticker on the cover.
 
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Changed all 4 of mine today. 1/2 was the only sensor that was a pain, it did not want to come out and once it did the new sensor would not thread all the way in. I grabbed a thread chaser at O’Reilys and cleaned up
the threads and the new one went right in.


Not sure if it’s been mentioned before but it would probably be a good idea to go ahead and get a thread chaser with everything else to be ready.


This is the one I got at O’Reilys
Lisle 12230 Oxygen Sensor Thread Chaser
 
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Only 100 or so miles since the sensors were changed but everything seems to have smoothed out. Previously at start up and at stop had a bit of a shake and I could feel some vibrations through the floor board and in the pedals while driving. These have all been eliminated and no CEL yet. As of now I’m calling it a successful swap.
 
I cannot get mine to break loose. The socket referred to earlier in this post is the one I am using. Any tricks? I sprayed liberally with penetrating fluid. Maybe I need to get some of that Kroil.