I've just ordered an O2 sensor to hopefully get rid of an error code but don't know what size socket I need to remove it - I tried measuring with a caliper this morning but not sure I got an accurate reading. It would be good to know so I can get the socket ordered before the sensor arrives so if anyone can help I would be very grateful.

 

Short answer: 7/8 standard or 22mm metric.

There are lots of options here. The catch is that the sensor has wires on it, so a "special" socket is typically used. The socket has a slot to pass the wires. Unfortunately, this slot make the socket weak, so if the sensor is somewhat stuck, the socket opens a bit and slips. When combined with cheap tools that are not terribly exact on the size, and this turns into a frustrating experience. So folks sometimes "commit", cut the wires and use a normal socket. Then there is access. The top sensor would use a different tool than for the lower sensor. Altogether, over time, you probably will end up with more than one.

What is the code, and what sensor are you replacing?

 

Yelp what fmertz said. My lower right sensor went out on my 03, I lost what sanity I had left trying to get it off with a sensor socket, finally cut the wire and used a deep 22mm and it came off in 5 seconds, going back on was easy.

See here for details

https://www.jaguarforums.com/forum/x...rs-how-149326/

 

Cheers for that - I knew it needed a slotted socket but I only have one so wasn't sure about the size. Sounds like I might be needing to cut wires though, or just get it to the Indie I use and get them to do it for me - the car is with them on Thursday for tyre fitting anyway!

 

I also cut the wire and used a socket.

I had tested and found the heater was blown so the old one was scrap anyway.

(STR - not your car, but same idea.)

 

did you all take off the catalytic converter or did you figure out a way to reach them still attached to the exhaust?

 

Access under the car was OK. (Remove undershield aka belly pan if fitted.)

 

I took my car to the local garage I use rather than do it myself. He said he used a lot of extension bars and after leaving it to soak with a release spray for a couple of hours it came out quite easily. Charged me £45 labour to do it.