My car is making this ticking noise when I turn it on, but also I hear it through the side wheel. When I open the engine I can hear it and the noise doesn't get louder. When I drive I cant hear it, but when it is idling is when I hear it a lot. I went through drive through today and couldn't help but hear the noise. It doesn't sound very good.

 

My XF makes the same noise. In fact, if you google "Jaguar 35t ticking noise" you'll see it's pretty common. I've got an appointment tomorrow to see if the dealer can find the source, but I expect they'll say it's "operating as designed". I'll let you know.

There is a TSB regarding the XEs with the same engine that replaces an "earthing strap". https://www.xeforums.co.uk/viewtopic.php?t=4638