Anybody know where it is located? I wish to replace it...I tried TOPIx but could not find its location...

 

One of the joys of having a 'new' vehicle is locating everthing; so as not to spoil your fun (for a 2007 XK) I'll give you a clue! Look under the hood on the passengers side (LHD), that's a good place to start! so much better than our XK8.
Before you ask the Air Cleaner is another matter; try removing the left front fender liner! It's easier after removing the LF wheel.
Not sure way it's there other than one road test said " Jaguar wants you to hear the intake roar!"
There you have it and more......

Hope this helps, Cheers, Adrian

 

Same as XJ's?

 

It is under the right, pass side panel next to the firewall under the hood. Just be careful opening the little door to pull it out. I broke the hinge on mine trying to get it out for inspection.