Sure. It'll be a couple of weeks, but happy to report back. The fact there's no wiring harness that I could see is particularly concerning.
The Official Jeep Wrangler TJ Oxygen (O2) Sensor Thread
- Thread starter Chris
- Start date
I have a 2000 4.0L, built in Feb, with 4 o2 sensors, have all 4 sensors as listed above however for b1s1 the ntk 23122 is too short to reach the harness on top of the intake manifold!
do these come with different length wires?
do these come with different length wires?
I think they do make a sensor with a longer wire, but I don't know if it's listed any where, your best course of action is to call NGK/NTK directly, they are very helpful and knowledgeable.
I just purchased 2 Denso O2 sensors for my 1999 4.0L TL. After reading some of the above feedback I am feeling better about replacing these but am now questioning using the Denso product vs the suggested NGK/NTK.
Does anyone have any experience with Denso components?
Part Numbers
Upstream 234-4076
Downstream 234-4078
Does anyone have any experience with Denso components?
Part Numbers
Upstream 234-4076
Downstream 234-4078
I just purchased 2 Denso O2 sensors for my 1999 4.0L TL. After reading some of the above feedback I am feeling better about replacing these but am now questioning using the Denso product vs the suggested NGK/NTK.
Does anyone have any experience with Denso components?
Part Numbers
Upstream 234-4076
Downstream 234-4078
Does anyone have any experience with Denso components?
Part Numbers
Upstream 234-4076
Downstream 234-4078
The consensus has pretty much been, using anything other than the NGK/NTK sensors has been hit or miss. They may or may not work out for you. The 2 sensor systems are a little less finicky than the 4 sensor systems but that's not to say they wont trigger a CEL.
HardSell
TJ Enthusiast
Here's what solved the problem for me. They've gone up 5 bucks in the past 6 months. Be careful with the tiny spade connectors. They get pushed back through the connector and will CEL you if all are not making contact with the female inputs. Push the cable along with the connector when connecting.
https://www.amazon.com/dp/B06XKGVFN4/?tag=wranglerorg-20
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OP
Thanks, I'll be sure to add this to the first post!
Threw my first CEL today (am I officially a TJ owner now?): P0138. Cleared it, but haven't driven it yet. Order all four O2 sensors anyway.
HardSell
TJ Enthusiast
You now are official. Wishing you luck. I've been fighting the randomly rotating CEL issues for two years now. Eliminate one issue get two more. I've discovered there's a window of 10-30 miles when I get an all clear and ready for testing from my OBD2 scanner. I'm up for testing in 3 months. I plan to rush in to test while in that corridor. When I bought the Wrangler a couple years ago the dealer got it to pass despite a P0174 showing. My guess and I say, GUESS is: as long as the O2 sensors pass, you'll get a pass. This may vary among states. Many states have stopped testing altogether. My next "Wrangler" will most likely be an EV if I'm not dead. EVs today aren't good enough and over in the JL forum a lot of owners are stranded at dealerships struggling with emissions issues. So, I'll stay with the devil I know.
It's funny how they show Idaho required in "some" areas... The vast majority of the state does not require it, and I have been hearing whispers that it wont be long until it's gone all together.
HardSell
TJ Enthusiast
I have that done every couple years for DOT compliance, but thanks. Ever since Washington State dropped their testing Idaho has been quietly talking about doing the same.
I did say whispers not voices.. I listen to the whispers in some circles to see what could be changing.
The voices on the other hand.... I almost never listen to them any more. They have a tendency to get me in trouble.
HardSell
TJ Enthusiast
I'm amazed Washington did that. Idaho is over due, but 'fornians are fleeing to Boise and bringing it all with 'em. Next thing Oregonians will be pumping their own gas. God forbid!
HardSell
TJ Enthusiast
Passed emissions! Before needing to chance the 20-30 mile "forgiveness" corridor when CEL light stays off while all other parameters show ready, I discovered that the factory connector wired to the downstream Bank 1 harness had offset female catches for joining the cables. This requires the O2 connector plastic jacket to match the factory offset jacket. The extension connectors from Amazon have large symmetric keyhole fittings and therefore are more universal allowing a variety of O2 offsets to be connected while the 4 wire plug connectors are all the same. These offsets are difficult to notice while connecting, lying on your back under the Jeep. Two years ago, shortly after I bought the TJ, I began to get downstream codes showing catalytic converter failures. So, I mentally prepared to replace the whole expensive set up when the time came. In the meantime I played with both downstream sensors and the pesky CEL to see if I could establish a failure pattern. The first failure sequence involved Bank 2 downstream. I replaced the nasty old O2 sensor and for good measure, bought one of those platinum wool 90 degree extenders along with an extension cable never noticing the factory offset connector jacket design because the extension cables had universal catches fitting together without protest. The three components totaled less than $50 making me a happy do-it-yourselfer. CEL did not return. Bank 2 downstream solved! (so I thought) I cleaned up the old O2 sensor and stored it away. Steel wool and paint thinner. Looked new again. Six months on... Bank 1 downstream flashes catalytic failure. So, I swapped out the 90 degree platinum wool extender from Bank 2 not changing out the Bank 1 sensor. I had never actually tested the new sensor on Bank 2 by itself. So, Bank 1 clears; then a few drive cycles later, Bank 2 flashes an O2 lean code. I feel up and around the Bank 2 catalyst tank and patched what I thought was a concealed hole in the pipe joining the catalyst tank. Previous owner drove in mud up to the headers, must have had it detailed but leaving the cats and a foot of exhaust pipe with a half inch of baked on adobe. CEL persisted with the new lean code for Bank 2 downstream. In removing that O2 sensor I discovered one of the tiny male spade clips in the extension connector was just short of making contact with its female insert. Yup, it had worked itself out over a couple trips. So, grabbing the wires and pushing all four spades and making sure they were seated into their sockets once again solved the CEL issue with Bank 2. There was no hole in the exhaust pipe. So, a long trip once again fires up the CEL Bank 1, this time a rich code. Noting that all this time my highway gas mileage has been progressing from 14 mpg when I first bought the rig to just under 18 mpg! City, remained a flat 15 mpg. For a year I ignored the CEL while the Jeep ran great. So time passed and coming emissions won't pass if I'm unable to synch the CEL quiet corridor with emissions coming due. Having nothing to lose and the Bank 1 affair is very easy to access, I pulled out the old stored O2 sensor to try it out on Bank 1 discovering the connector issue mentioned above....damn! I'm bull headed. I took some wire cutters to the salvaged O2 sensor connector, clipped and trimmed away all the plastic coupling surrounding the four plugs sending signals to the PCM. The connection now was not only visible, but was tight and secure. CEL stayed off for the required driving cycles. I got it passed and it has not returned. So, I netted a working extra O2 sensor, a two year pass and avoided a cat replacement in freezing weather. Now, about that OPDA thing....
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Finally took care of this. All in, took about 1.5 hours between wiggling my fat ass under the Jeep and doing vehicular yoga to get arms up in there in a position to apply any kind of torque on the socket wrench. By far the easiest vehicle I've worked on to replace all the oxygen sensors.
So I'm looking into changing out my o2 sensors, but I'm a bit confused at what I'm seeing from the PO.
(97, 4.0, MT... 2015 Blown Transfer Case, shredded wiring)
The upstream sensor looks proper, but the downstream is what I'm confused at.
Is there a good reason that the downstream would be shoved up into a random hole in the frame?
I think I found where the downstream is supposed to connect. Is this correct?
(97, 4.0, MT... 2015 Blown Transfer Case, shredded wiring)
The upstream sensor looks proper, but the downstream is what I'm confused at.
Is there a good reason that the downstream would be shoved up into a random hole in the frame?
I think I found where the downstream is supposed to connect. Is this correct?
Bank 1 sensor 1 (upstream) should be just below the flange, mating the pipe to the manifold, bank 1 sensor 2 (down stream) should be between the catalytic converter and the muffler... That being said I suppose it's possible someone could have installed a different catalytic converter that has it "in" the body of the cat???