I have been trying in vain to find good instructions and/or a video about changing the upstream O2 sensors on a 2003-2006 XK8. There is a ton of info about all other models. You can see the sensors and probably get to them with an O2 sensor socket after removing the intake tube on one side and the coolant reservoir on the other.
I can see no way to access the electrical plug connector anywhere.
Can any of you help?
Thanks

 

Which side?
Either way, put the bonnet in the service position and get a thick blanket or several blankets to lay on, The connections are behind a shelf right in the middle of the back of the firewall. They are on a thin metal stud that you lift then off. Be sure to tie a string to the connection so you can thread it down to the sensor and untie it to put the new one on to pull it up in place, still takes a bit of threading it through the other wires.
Oh, unplugging the connection, be careful, don't pull on the wires, they require a push on the clip to release.
Getting to the one under the reservoir requires a flex head ratchet and correct socket but can be done with a plumbers wrench.
Do you have the right sensor numbers.

 

Greg, here is a great DIY thread that has lots of information on installing both sides but Shoreguy gave a really good write up on his adventure.
DTC1647 Did I create a gremlin? - Jaguar Forums - Jaguar Enthusiasts Forum

 

I have a 2003 xk8, and did mine last year. The only problem I had was that I must have pushed on the octopus hose. Because of the age of the car, the o rings inside the quick release fitting were hard. I had a coolant leak. Put new o ring in and fixed the leak. Pain in the backside to release the quick release, but done now. No leak.

 

I went through the dashboard to get a breaker bar on the sensor. see photos in this thread https://www.jaguarforums.com/forum/x...d-dtcs-276088/

+1 on tying string to the connector so you can fish the new one through when changed. the connectors are behind the throttle body and a bitch to get to, but accessible. helps to have nimble fingers. A small, well-trained human may be helpful.

 

I did that PITA job recently, the O2s themselves aren’t so bad but the connectors can be a real nuisance.

The sensor plugs are light grey. The right bank is mounted on the junction box to the rear right of the throttle body, the left bank is mounted on a mounting panel in front of the firewall.




Unfortunately the sensor plug clips on to the mounting panels, so you can’t just unclip the connection, you have to dismount them from the mounting panels. The problem is that the mounting panel metal clip holding the connector points downward so you really need to unclip them from below.

You can try a small screwdriver from the top but be careful not to break the plastic O2 connector housing. I made a small release tool for this to get underneath the plug mounting panel and release the connectors.

Even so, they will test your patience.

For the O2 sensors I went in straight from the top with a split 22mm O2 sensor socket and 22mm crowfoot. HF sell a really handy slim long ratchet which is ideal for these tight spots.



The plug release tool is made from a strip of 4mm stainless bent to fit and with both ends sharpened on a grinder to slip under the connector plug mounting.

Finally – if you do break the O2 or harness connector then let me know, I have replacement male, female plugs and pins if you need them.