I just completed this repair. On my 11 year old 2011 with about 260k miles. This is the first time anything about this repair has been touched, so I was unnecessarily worried about the O2 sensor. I fought most of the sensor off, but the center piece wouldn’t budge. I used a Dremel in an attempt to cut and chisel it off, but wouldn’t get a good angle. I ended up getting a small gear puller and a 10mm socket because I t was the biggest that would fit through the puller. I notched two sides off. Think slotted screwdriver but reversed. I then drilled out the back of the socket so that the post of the puller would be captured. The socket stabilized the whole assembly so that the post wouldn’t slip off of the shaft. I got it off a little before the puller’s center post bottomed out on the socket, so I used my Shopsmith disc sander with 180 grit to grind the threads off and extend the narrow portion of the post long enough to reach through the sensor completely.
Here’s where grabbing the $30 flexible shaft for my Dremel could have been a very simple solution.
I removed my O2 sensor easily with a large adjustable wrench I bought about 25 years ago to adjust my BMX crank. Today was the second time I used it.
I screwed around for about 5 hours, so here’s how I would do it next time.
Someone made a puller that threads onto the sensor and has a bolt that goes down the center, directly pulling everything all at once. Wish I’d have found that before destroying them in attempted removal. I’d try to locate or fabricate one, remove the O2 sensor l, pull the NSS, put the new one on, test position, be done in 10 minutes.
If no neat puller,
Remove O2 sensor.
Use spring loaded center punch, then Dremel with flex shaft and proper bit to put a divot on the shaft.
If I could find or tweak a puller that fits over the entire sensor, I’d use it now.
If not, I’d use a metal cutting wheel on the Dremel to excise most of it and expose the center piece which is rusted to the shaft.
Use small gear puller to remove what’s left.
Install new sensor.
Install O2 sensor.
Test shifter for proper positions.
Done in an hour.
Here’s the puller I used. It just fit when I pulled the shaft toward me. It has maybe 1/4” of side to side play. I had to grind down the center post to fit through the sensor. I just ground and rotated for a few seconds before dipping in water to cool. It took maybe 5 minutes or so, testing for clearance on the new sensor. By putting a divot on the shaft and clearancing the center post, you can save your 10mm socket sacrifice because the assembly will be stable.
Feel free to PM/tag me with questions. I’m no pro, just handy, and found the available info lacking. Blasted reliable vehicles! Please note that my lack of experience with this led to a period of hydrating reflection on how I could have done this better and hope that people find my ramble helpful. Maybe I’ll clean it up later when my hydration wears off.
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