I disagree. Hardly anyone ever changes any of them as you can tell from the quite few posts out of the tens of thousands.

The problem is not engine damage it's catalytic converter damage which leads to failure. Now your car won't pass emissions inspection because of the bad cat. You don't want to turn a simple fairly cheap problem into a much larger and more expensive repair. Just not smart!

You must not have an S Type?? The O2 sensors are very simple and quick to change. One of the easiest cars to change I have ever worked on.
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Does anyone know the best replacement O2 sensor for a 2000 Jaguar XK8. I ordered a Denso but they shipped me the after cat sensor in error.
Fun getting it out, but after an hour all was well. Ended up using a 7/8 box end wrench, with another wrench in the open end section for additional leverage.
I guess now being in Canada, I will have a week waiting for the right O2 sensor to arrive, which to company I purchased this item from does not have inventory.