Oxygen sensor plug extension

[Ksat]

Has anyone ever sourced an O2 sensor plug extension that will work with the upstream for the 3.7? The driver's side is next to impossible to unplug and I'd rather not have to go through the difficulty of doing it again.

 

[Ksat]

Well, in case anyone else is looking for one, I think I found it:

https://www.amazon.com/APDTY-Extension-Universal-Chrysler-Challenger/dp/B0793FDNG9

 

[Offroad Bob]

I have a 02 Liberty Sport with the 3.7 and had to change the drivers side, upstream o2 sensor two years ago. I got the old out, but not without a struggle. And as you say, it was impossible to get the new one one plugged back in and reinstalled. If whomever designed that wiring harness would have been anywhere but sitting at a desk or the engine sitting on a bench, they would have seen this problem and added about 6” of wire to either lead. The plug is behind the oil filter, right below the power steering pump, exhaust manifold and is tucked right up against the engine so it’s virtually impossible to get in there. I ended up struggling for 2-3 hrs before deciding there had to be a better way. I took my old sensor and looked at it and there are 4 wires coming out the plug going to the sensor. Two white wires that are side by side and a black one and a grey one also. I asked a local Local mechanic about splicing the wires and he said it was special wire and you could not splice it and he had never heard of an extension being available. I went ahead and cut one of the two white wires on the old sensor anyway to see what type of wire it was. Turns out it’s just regular stranded wire ! So labeled each wire as they came out of the plug and put the new sensor next to it and labeled those wires according and they were a perfect match. The two white wires are next to each other as they exit the female plug and the grey and black one are in the next row. I made sure and orientated the old and new plugs next to each other so I didn’t cross the white wires up. One by one I cut the wires on the new sensor and left them about 6” long. Then I cut the ones on the old sensor about the same length from the plug and then the patched them together. I slid heat shrink tubing up each wire first, then soldered them together one by one. After hooking them all up I made sure they were sealed up good. Then I reached down behind the power steering pump and squeezed my hand down in there and was able to grab the plug in off the harness. I could hold it and then reached down with my other hand and was easily able to plug it up ! Then I just dropped it through where the wires originally ran. Then I crawled back under the Jeep again. I put about 8 reverse turns on the new sensor and then threaded it into the exhaust. You must do this so your wires won’t wind them selves up. Then tightened it down and fired it up. I had already cleared the codes from the OBD and it ran like a champ. This was two years ago and all is still good ! If I could have seen the hack engineer that designed that harness, I believe I would have strangled him !! If they had added 4 or 5 inches of wire to either the plug off the harness or had made the new sensor wires longer, it would have saved me about 4 hrs. I’m sure I’ll get scolded by some on here for doing it this way, but **** it worked ! If it didn’t work, I would have just gone back and bought another sensor and try to get it back in there somehow. I also heard that you needed to use OEM Mopar sensors. I had planned on using Bosch as they are a pretty good brand in my opinion and a little cheaper, but was advised against it. I went to Moparpart.com and ordered from them before starting this ordeal !
It worked perfectly and between the new and old sensor, you have all the needed materials needed. I’ve attached a picture of the old plug.
I hope this helps !
Bob
Thank you for reading !

 

[Ksat]

Many Chrysler vehicles use whats called a bias voltage on the sensor that an aftermarket product may not incorporate into their design. This video goes into more detail about it:

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Ordinarily when it comes to auto parts I just buy whatever is cheapest but, when it comes to the O2s, you really need to stick to the NTKs. Regarding Bosch sensors, I have heard perhaps more complaints about those brand of sensors not working correctly on vehicles in general more than any other.

Congrats on successful splicing your the O2 wires. I would suspect the most important thing to make sure of when doing that is use wires that use a high temp insulation on them.

 

[Arthur McKenna]

I just replaced my 02 sensors today, and yeah, the connector on the drivers side upstream is a ***** to get to. It's a one ******** (insert joke), and if you have hams for hands forget it. I have pick-pocket hands and fingers, and I barely got it done.

 

[Rough]

Did one last year, used a long screwdriver and Harbor Freight long reach hose grip pliers to unplug the sensor. Takes a bit of time but it's doable.