The Official Jeep Wrangler TJ Oxygen (O2) Sensor Thread

[Rico Suave]

Question, got a 98 TJ that I have replaced many things and fixed issues based on this forum. Having said that, here is my question. I still have the shudder on take off. It’s an auto so no clutch. Did mounts for trans and engine, u joints, angle is fine, control arms etc...only thing left that I haven’t tried was a bad cat. I don’t need one where I live, but if I cut it off and piece in a pipe what do I do with my O2 sensor?

 

[Captain Phoenix]

Question, got a 98 TJ that I have replaced many things and fixed issues based on this forum. Having said that, here is my question. I still have the shudder on take off. It’s an auto so no clutch. Did mounts for trans and engine, u joints, angle is fine, control arms etc...only thing left that I haven’t tried was a bad cat. I don’t need one where I live, but if I cut it off and piece in a pipe what do I do with my O2 sensor?

Call this guy and talk to him. It's not cheap but he can delete the post cat O2 sensor from your computer so you can run without it without throwing a code.

http://www.bgperformance.com/b-g-pro-tuner-software/

 

[SPECWAR]

It’s a pretty simple permissive to shut off the post cat 02’s. Spent a few years with the Superchips Ford custom tuner and participated in a lot of his work.

 

[Padre]

In need of the wiring schematic for the o2 sensor of my 97 TJ . I need to create my own adapter as mine is trash. Does anyone know which wires goes into 1,2,3,4 position? I have searched the internet forever. I just need to know which wires go to which pin. Any help?

 

[SoCalTJ]

+1,000,000 for the tip on the o2 socket tool!! Really glad I came across this post. Tool made the job much easier.

 

[LNA1824]

What are Bank 1, Bank 2, etc.?
Since this question pops up from time-to-time, here's an easy to follow diagram that illustrates what they mean when your OBDII code scanner (or manual) tells you something like "O2 sensor, Bank 1, Sensor 2":

View attachment 12208


What does upstream and downstream mean?
Simple, upstream means the O2 sensor is "upstream" of the catalytic convertors, meaning before the catalytic convertors. Downstream means the O2 sensor is "downstream" of the catalytic convertors, meaning after the catalytic convertors.


What brand of O2 sensors should I use for replacements?
Pay close attention to this one so you can do it once and do it right! The Jeep Wrangler TJ is extremely sensitive to all oxygen sensors other than NGK / NTK. Bosch O2 sensors and all the others (including the crappy Chinese brands you'll buy at your local auto part store) are very well documented as not working properly with our TJs. In other words, you plug them in and you assume all is well, until you notice your check engine light isn't going away. This is almost always due to the fact that you didn't use an NGK / NTK replacement O2 sensor.


Okay, so why don't other sensors (i.e. Bosch) work on our Jeeps?
Glad you asked! Check out this video for a detailed explanation of why other brands of O2 sensors don't work on our TJs:

So which O2 sensors do I need?
I'm going to break down which sensors you need based off what year your TJ is. The part numbers (and information) below were taken directly from the NGK website, so you can assure it is 100% accurate (even double checked each individual year and model before writing this thread).

4 Cylinder Engines​

​

1997-2000​

NGK #23506 - Bank 1, Sensor 1 (Upstream)​

NGK #23151 - Bank 1, Sensor 1 (Upstream) (1998 ONLY)​

NGK #23099 - Bank 1, Sensor 2 (Downstream)​

​

2001-2004​

NGK #23138 - Bank 1, Sensor 1 (Upstream)​

NGK #23141 - Bank 1, Sensor 2 (Downstream)​

​

2005-2006​

NGK #23159 - Bank 1, Sensor 1 (Upstream)​

NGK #23159 - Bank 1, Sensor 2 (Downstream)​

​

​

6 Cylinder Engines​

​

1997-1999​

NGK #23151 - Bank 1, Sensor 1 (Upstream)​

NGK #23099 - Bank 1, Sensor 2 (Downstream)​

​

2000​

NGK #23122 - Bank 1, Sensor 1 (Upstream)​

NGK #23506 - Bank 2, Sensor 1 (Upstream)​

NGK #23099 - Bank 1, Sensor 2 (Downstream)​

NGK #23099 - Bank 2, Sensor 2 (Downstream)​

​

2001-2003​

NGK #23139 - Bank 1, Sensor 1 (Upstream)​

NGK #23138 - Bank 2, Sensor 1 (Upstream)​

NGK #23142 - Bank 1, Sensor 2 (Downstream)​

NGK #23141 - Bank 2, Sensor 2 (Downstream)​

​

2004​

NGK #23137 - Bank 1, Sensor 1 (Upstream)​

NGK #23135 - Bank 2, Sensor 1 (Upstream)​

NGK #23132 - Bank 1, Sensor 2 (Downstream)​

NGK #23531 - Bank 2, Sensor 2 (Downstream)​

​

2005-2006​

NGK #23018 - Bank 1, Sensor 1 (Upstream)​

NGK #23160 - Bank 2, Sensor 1 (Upstream)​

NGK #23159 - Bank 1, Sensor 2 (Downstream)​

NGK #23158 - Bank 2, Sensor 2 (Downstream)​

​

​

Misc Installation Notes
When installing new O2 sensors, be certain to use some anti-seize on the threads of the new O2 sensors! This is important, and will save you a huge headache should you ever need to remove them in the future.

In addition, a O2 sensor socket will greatly aide in the installation and removal of O2 sensors. I recommend this one.

Hey everyone! I know this thread is a few years old but I'm now having this issue with my Jeep. Chris, can you please tell me how many O2 sensors my Jeep has? It's a 2006 Wrangler Unlimited. Thank you in advance!!

 

[AMS417]

Hey everyone! I know this thread is a few years old but I'm now having this issue with my Jeep. Chris, can you please tell me how many O2 sensors my Jeep has? It's a 2006 Wrangler Unlimited. Thank you in advance!!

2006 has 4 O2 sensors. Two in the manifold, and 1 each below the pre cat.

 

[Rooscooter]

2006 has 4 O2 sensors. Two in the manifold, and 1 each below the pre cat.

.... and 3 of them are really easy to get at.... the 4th one requires a little work.

 

[Chris]

Hey everyone! I know this thread is a few years old but I'm now having this issue with my Jeep. Chris, can you please tell me how many O2 sensors my Jeep has? It's a 2006 Wrangler Unlimited. Thank you in advance!!

Four

You will want to read the original post.

 

[Pullski]

Hey Chris! I know this thread is a few years old but my Jeep is having this exact issue. O2 sensors were all changed about 4 months ago and now the CEL came on. Can you tell me how many sensors my Jeep has? It's a 2006 Wrangler Unlimited. Thank you in advance!!

4...2 above the pre-cat and 2 just beyond the pre-cat. What code is the CEL throwing?

 

[LNA1824]

2006 has 4 O2 sensors. Two in the manifold, and 1 each below the pre cat.

thanks for that info! A mechanic said clearing the code might work, so I'll try that 1st. If not, i have to get ready for the inevitable!! Thanks again

 

[Pullski]

thanks for that info! A mechanic said clearing the code might work, so I'll try that 1st. If not, i have to get ready for the inevitable!! Thanks again

What code is coming up? Do you know how to read them?

 

[Fishtaco]

thanks for that info! A mechanic said clearing the code might work, so I'll try that 1st. If not, i have to get ready for the inevitable!! Thanks again

If Its only the o2 codes just clear them first and see how long before they come back that's if they do come back!
I had both o2 codes on a CEL shortly after buying my 06 8 months ago, I cleared the codes while waiting for 4 new ones from Rockauto and they are still in the shipping box in the shed!

 

[LNA1824]

What code is coming up? Do you know how to read them?

P0158

 

[LNA1824]

If Its only the o2 codes just clear them first and see how long before they come back that's if they do come back!
I had both o2 codes on a CEL shortly after buying my 06 8 months ago, I cleared the codes while waiting for 4 new ones from Rockauto and they are still in the shipping box in the shed!

 

[LNA1824]

Fingers crossed

 

[Doughboy00008]

My issue/fix. I have a 2000 TJ California model, 4 o2 sensors. Check engine light has been on for years. Changed all 4 sensors because of codes over the years. Used ngk. It was pulling 3 codes for 3 out of 4 bad sensors. Finally cleaned the ground at the block where the dip stick mounts. Also ran a direct ground from the battery to the same location(read in another post). Drove 100 miles since the battery was disconnected and still no check engine light. Longest it’s been in the last 5 years. Also passed inspection. Hopefully that did the trick

 

[inkedrose]

This was helpful but Im still stuck. Replaced both upstream and trying to replace the two downstream. They are frozen! Been using an O2 socket, breaker bar, PB blaster, heat. Can not get them to budge!! Anyone have any other tips? Scared I'm going to need to replace the entire piece with the cats? Heard someone say drill and tap new holes, does that really work?

 

[reddvltj]

This was helpful but Im still stuck. Replaced both upstream and trying to replace the two downstream. They are frozen! Been using an O2 socket, breaker bar, PB blaster, heat. Can not get them to budge!! Anyone have any other tips? Scared I'm going to need to replace the entire piece with the cats? Heard someone say drill and tap new holes, does that really work?

Yes you could drill new holes and weld in new bungs for the sensors. Have you tried using a box end wrench and a cheater bar to get the lowers broke loose?

 

[AaronPaul]

Added a bunch of info to this thread. This should hopefully serve as a great resource for all the O2 sensor related questions we see.

is NGK and NTK the same thing. I only see NTK on Rock Auto? Sorry if that is a dumb question