My rear O2 is out...gotta get something... unplugged it for now but it's still hitting limp mode. Probably going to order a set of the Walkers.
-Mac
-Mac
The Official Jeep Wrangler TJ Oxygen (O2) Sensor Thread
- Thread starter Chris
- Start date
Rear O2 (downstream) shouldn't be causing drivability problems? It's just a monitor for the condition of the cat, IIRC.
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I just ordered 2 ntk23099 on Napa. We'll see if they ship or not.
The kicker is the upstreams on the 2000 Cali.
Found something recent on a Cherokee forum about 23506 getting replaced with a 23179. When I look at 23179 the plug doesn't look familiar on the stock photos associated. Could be photo doesn't represent the product, I also could.juat be unfamiliar with this year's upstream, haven't had to mess with them yet.
Yeah that's the only code...need to check fuel pressure. Guessing the pump or regulator is going out.
-Mac
Entirely possible...but it runs really well for a bit when I turn off the Jeep. Plugged cats don't improve on reboots. =)
-Mac
When you say a bit. Is that until it warms up and switches to closed loop? Or does it start running poorly while it's still warming up?
Might be worth a shot to remove the cat and seeing how it runs.
Cold start it has to warm up. Reboot gets me 30 seconds to 2m of running. Was enough to limp to work. I can probably loosen the exhaust bolts from the header to the downpipe without too much drama. But I think I'll make a run for home while it's cooler.
-Mac
Did anyone else have issues with the 23141 for bank 1 sensor 2? I have a 2004 TJ and the harness didn’t quite fit right. The new sensor plug had a slot that was off centered. I had to shave off the male edge of the existing harness to get plugs to connect. Made me think I had the wrong sensor… but don’t think I do. Seems to be fine.
looks like I have the wrong sensor. Should have been 23132. Will this be a problem? Should I correct?
You can call NTK tech support and they can tell you if the sensors are compatable outside of the connector.
Alright O2 Lords, I need your help.
2000 4.0. In May I replaced my muffler and tailpipe. I had to cut the old one off, and I was doing a lot of banging around down there. Install went fine though, everything running normally. Check engine light pops up. I don't have a code reader but my mechanic told me the code and it's showing the downstream O2 sensor. When I reset it, the check engine light will stay off for a couple days, but it always eventually comes back on.
A couple weeks ago I replaced the O2 sensor with a cheap one from Amazon, not NGK, and it's doing the same thing. No light for a day or two, then it pops up again. I'm now learning the cheap sensor was a mistake, but here's my question: if the cheap sensor is the issue, would the check engine light still take a few days to turn on? Or would it be immediate? I'm scared I did my cat in when I was banging around down there, but I'm assuming yall would always recommend getting a NGK in there before trying anything else.
2000 4.0. In May I replaced my muffler and tailpipe. I had to cut the old one off, and I was doing a lot of banging around down there. Install went fine though, everything running normally. Check engine light pops up. I don't have a code reader but my mechanic told me the code and it's showing the downstream O2 sensor. When I reset it, the check engine light will stay off for a couple days, but it always eventually comes back on.
A couple weeks ago I replaced the O2 sensor with a cheap one from Amazon, not NGK, and it's doing the same thing. No light for a day or two, then it pops up again. I'm now learning the cheap sensor was a mistake, but here's my question: if the cheap sensor is the issue, would the check engine light still take a few days to turn on? Or would it be immediate? I'm scared I did my cat in when I was banging around down there, but I'm assuming yall would always recommend getting a NGK in there before trying anything else.
First things first, is your Jeep Federal or California Emissions? 2000 was a transition year. Federal maintained only 2 O2 sensors, CA switched to the 4 sensor system. (I'm going to assume that you have Federal because you said you only replaced 1 down stream sensor.
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I've gone down this rabbit hole before, but I'm pretty sure mine is Federal. I'm only aware of one sensor after the cat. I'm assuming there's another one upstream, I've just never looked for it. If you look at some of my earlier posts, I've attached pictures of my exhaust. There's a chance my was replaced without pre-cats. I can't tell if they're original or not.
I can't remember if the VIN decoder will show if it's Fed or CA... But if yours was a CA emissions all 4 of the sensors would be visible from the driver's side looking down 2 above the pre cats 2 just below. The Fed emissions upstream is just before the cat.
This is what the 2000 Federal emissions (and export models) Exhaust Head pipe is supposed to look like. The pre-cats were only on the CA emissions until 2001.
But back to your problem. If you haven't experienced any noticeable decrease in power (like the exhaust is partially blocked) I would suspect the 02 sensor or maybe an intermittent wiring problem is the culpret. Unfortunately finding either NTK O2 sensor for the 2000 Federal emissions is nearly impossible. I would not trust Amazon sellers that say there's are "NTK" or "Mopar", as many people who have ordered from Amazon have shared their stories about the sensors coming in unmarked packaging. Last time I looked Rock auto was completely out of stock for the 2000 Fed model too...
I thought I remembered someone posting about an update to a couple sensors, and it's just a few posts back on this page.
your down stream should be the 23099 and according whom ever made the post that was screen captured NTK replaced that sensor and another with an updated part number, the 23179... You might contact NTK tech support to see if that's true or not..
https://wranglertjforum.com/threads...-tj-oxygen-o2-sensor-thread.4068/post-1384035
Ok, the upstream sensor is right before the cat like in that head pipe image you shared, so mine's gotta be Federal. My head pipe is shaped the same but there's not a bolt-on flange before the cat. It's all welded as one piece until you get to the muffler. I wonder if mine is aftermarket?
In any case, it sounds like potentially the 23099 or the 23179 would work?
In any case, it sounds like potentially the 23099 or the 23179 would work?
@reddvltj You were right about them being hard to find. I managed to find a Canadian site selling 23179s. Only 37 bucks after the conversion rate. We'll see if the site (and the sensor) works out!
I'm still holding out hope that the last person who posted about finding a potential replacement brand reports back with positive results.
wrangleras
New Member
Hi Guys,
I am wondering if anyone has used Denso or Walker O2 sensors (before the catalyst) on their TJ's.
I ve got a 2.5L TJ (1997) and am having hard times in deciding which of the 2 to use.
Do Walker or Denso work well with the TJ's? I know that i should be using the NTK 23506 but cant get of them anywhere on this planet
I am wondering if anyone has used Denso or Walker O2 sensors (before the catalyst) on their TJ's.
I ve got a 2.5L TJ (1997) and am having hard times in deciding which of the 2 to use.
Do Walker or Denso work well with the TJ's? I know that i should be using the NTK 23506 but cant get of them anywhere on this planet
Hi Guys,
I am wondering if anyone has used Denso or Walker O2 sensors (before the catalyst) on their TJ's.
I ve got a 2.5L TJ (1997) and am having hard times in deciding which of the 2 to use.
Do Walker or Denso work well with the TJ's? I know that i should be using the NTK 23506 but cant get of them anywhere on this planet
Without scrolling back through all the posts, I seem to remember someone saying they were going to try one or the other. I don't believe they have reported back as of yet.