NTK O2 Sensor Availability?

ScottV-TJ

New Member
Supporting Member
Joined
Nov 30, 2022
Messages
5
Location
Florida
New to the Forum.... I have a 1997 TJ 2.5L.

I have been reading threads on Power Loss/Sputtering and Backfiring problems. Replacing the O2 Sensors with a NTK sensors seem to be one of the common solutions.

https://wranglertjforum.com/threads/jeep-is-sputtering-and-backfiring.12758/

Problem is I cannot find the NTK 23506 (upstream) and NTK 23099 (downstream).

1) Does anyone have a source for the NTK 23506 (upstream) and NTK 23099 (downstream) O2 sensors? Are the NTKs still being manufactured?

2) If I cannot find the NTK/NGK O2 sensors is there another good alternative brand? (Other than the Bosh O2 sensors)
 
That's a tough one, both NTK and NGK say the upstream 23506 is on national backorder with no ETA. There's no need to search for the downstream 23099, it only monitors the catalytic converter and does not/cannot affect how the engine runs.

If you end up going with an alternative, make sure to avoid Bosch and low-end store brands. I'd probably go to my closest NAPA and go for their premium (most expensive) equivalent to the 23506 and cross my fingers. Don't let anyone talk you into a Bosch, they don't work properly in our Wranglers.
 
That's a tough one, both NTK and NGK say the upstream 23506 is on national backorder with no ETA. There's no need to search for the downstream 23099, it only monitors the catalytic converter and does not/cannot affect how the engine runs.

If you end up going with an alternative, make sure to avoid Bosch and low-end store brands. I'd probably go to my closest NAPA and go for their premium (most expensive) equivalent to the 23506 and cross my fingers. Don't let anyone talk you into a Bosch, they don't work properly in our Wranglers.

Thanks Jerry. I will report back with what I buy and if it solved my problem.
 
  • Like
Reactions: Jerry Bransford
Mopar lists different part numbers for 1997 vs 1998 in the parts manual:

1997:

2.5L
Upstream - 56027917

4.0L
Upstream - 56027916

Downstream for both - 56041108

1998:

2.5L & 4.0L
Upstream - 56041212

Downstream - 56041213AB

They went to using the same sensor for upstream on the 1998 4.0L and 2.5. Not sure what they did to make that happen but you might see if that 56041212 would work for you. Rockauto shows the 98 sensors as fitting the 97.

Usually the differences in O2 sensors is not in the sensor itself but in the wiring length. Usually it's the same 4 wires and sensor operation, just different lengths for whatever engine it goes on.
 
  • Like
Reactions: Jerry Bransford
Thanks everyone for your input. I ended up buying a Walker #350-34511 O2 Upstream Sensor from a local AutoZone. I will report back if I have any issues w/ the Walker O2 sensor.

After removing the old O2 sensor I noticed another wire that was burnt from not being secured. From the ground looking up, this wire (red arrow) runs next to the O2 sensor plug (blue arrow) and to the transmission (I think?). The wires inside the melted plastic sheath don't appear exposed. I tied up this wire and the O2 wire to keep them safe.

What is this cable and how easy is it to replace?

TJ Trans Wire 2.jpg


TJ Trans Wire 4.jpg
 
What I would do at this point is to closely examine the entire length of all four wires that lead to both O2 sensors for damage and replace/repair any burned sections. Something has to be causing your repeated O2 failures, my bet is you've got a damaged wire, like perhaps its insulation was melted by getting too close to the exhaust. This could be the root cause of your repeated O2 failures. Seeing the above photo just reinforces that thought for me.
 
  • Like
Reactions: Zorba
What I would do at this point is to closely examine the entire length of all four wires that lead to both O2 sensors for damage and replace/repair any burned sections. Something has to be causing your repeated O2 failures, my bet is you've got a damaged wire, like perhaps its insulation was melted by getting too close to the exhaust. This could be the root cause of your repeated O2 failures. Seeing the above photo just reinforces that thought for me.

Jerry, the burned cable/wires were on a different set of wires running to the transmission case (I think). It has a flat connector up top near the Upstream O2 sensor's round cable connector. What is this cable and is it easy to replace?
 
Jerry, the burned cable/wires were on a different set of wires running to the transmission case (I think). It has a flat connector up top near the Upstream O2 sensor's round cable connector. What is this cable and is it easy to replace?
If that cable connects to a manual transmission it connects to its neutral safety switch (NSS) which also controls the backup light. If it's the 30RH automatic it connects to its torque converter's lockup solenoid connector.
 
I'm now off topic, but based on the below thread it is my crank shaft positioning sensor cable that is burned. Sensor is still functioning fine (no codes or problems) but, I would like to replace it if is a simple replacement similar to the O2 sensor replacement. Thoughts?

https://wranglertjforum.com/threads/97-tj-sport-crankshaft-position-sensor-location.49343/

I don't want to wait for something to go bad at the wrong time.

Looking at the pic, and the fact the Jeep is still running fine, I think you may have just burned the insulation/loom over the wire and not the wire itself. I'd clean that up a bit, see how bad the wire itself looks and then just replace the loom (or splice the wire if actually burned)
 
  • Like
Reactions: ScottV-TJ