I went to replace the upstream O2 sensors on my 2006 Jag XK8 and see the sensors themselves are not too awful to get to, but the electrical connectors sure are. No idea what Jaguar was thinking when they tucked them up where they did given they are supposed to be replaced every 60K miles. They are on the firewall, and in front of them is a metal bracket, and in front of that is some sort of electrical component with some big wire bundles attached to it.

What's the trick to accessing and disconnecting the connectors? Do you first need to loosen or remove that big component, or does that even help?

Thanks!
Doug

 

Doing mine on my '99 4.0L this afternoon. A quick look before ordering the parts didn't appear too be an issue. Have you done your replacement yet? Anything to offer?

 

Mine is an 02 XKR, your results may vary.
I did this a little over a year ago. From memory, I had a layer of comfort atop my engine, then laid belly down on it. Thus, both needed hands and arms were somewhat free to reach and move. I probably also used my rechargeable 18650 Li-ion LED headlamp.
FWIW: I did a Bosch sensor replacement which has been flawless, but if I had to do it over, I would op for the general consensus on this forum to go with a Denso 02 sensor.

 

there is a hole, i think by the gas pedal that runs straight to the sensor. You can use a long shaft to go straight to the sensor and take it out. I know there are pictures or a youtube somewhere on how to get it done. I

 

I took a quick look and didn't see such a hole. I know there is an access panel for the brake light switch but would appreciate more info on this for the O2 sensor electrical connectors.

 

I changed on of mine (drivers side,downstream) earlier this year. You're correct, the connectors are a pain to get to. If I recall correctly, I managed to remove the connector (plug and socket) from the bracket, and bring it a few inches forward into the engine bay, where it is easier to work on disconnecting/disconnecting. As said above, put some thick blankets or padding over the fender and the motor - you are going to end up lying on them.

Also: when you disconnect the old O2 sensor, tie a piece of string or cord to the connector, and pull it out through the bottom, down the side of the transmission (so the string follows it, with the other end tied off in the engine bay somewhere.

Then remove the string from the old sensor connector, and then use it to pull the connector (and cable) on the new sensor back up into the engine bay. This is the only way you'll get it routed correctly...

One final thing: On my car the 4 connectors (which are on the same bracket) were NOT in the same order as shown in the service manual (upstream and downstream positions were swapped). It may be someone had swapped them in the past, but I think they came from the factory like that. Make sure you get the correct connector!

Good luck - it took a week for the scatches on my arms and wrists to heal after doing this!

-Steve

 

here you go

https://www.jaguarforums.com/forum/x...cement-115991/

 

Fantastic tip for early 4.0L cars but does not apply to the 4.2L cars. On the later models the sensors are straightforward to get to, it's the electrical connectors that are not.

 

Steve,

Thanks and I happened to triangulate your approach. Before reading your reply I had rediscovered in my file Gary VanRemortel's excellent 2003-21006 Jaguar XK8 doc I had printed off years ago and read it again. On page 16 he covered O2 sensor replacement, noting:

The upstream O2 sensors have gray connectors and the downstream black connectors
Lift each mated connector straight up off its metal mounting tab. They will pop up with a sustained direct upward force..
Once off the tab, there will be enough cable slack to squeeze the locking tab on the end of each sensor connector and unmate them.
Some have disconnected all sensor connectors at once and reconnected them wrong, don't be that guy.

Best,
Doug