Hey guys..After lots of work done on the cooling system on my XFs/c. New aux coolant pump,s/c coolant pump,new hoses all round(including the bugger under the supercharger),expansion tank and gaskets and ducts i was still getting more heat in the wrong places. I was hesitant to buy new thermostat because i was told i had to buy the housing too. So i just found the thermostat (AJ811788) without housing. Installed it and what do you know she is all better. Well she will be once i have run her a few miles. Did a reset on the battery so off i go to see if all goes back to normal.
Thermostat cost from Jaguar dealership in New Jersey. $90..Little cheaper online but i managed to get it same day so happy to go pick up.

 

Bear in mind that the water outlet containing the thermostat is made of plastic and can only endure a finite number of cold to hot cycles before failing. The thermostat seal can also fail causing a DTC to be set due to coolant bypassing the thermostat.



It's a good idea to replace the water outlet with the thermostat every time the coolant is changed.

 

NBCat..my housing is metal not plastic so all i change is the thermostat and O ring seal.

 

Sorry, my mistake! I didn't notice the 'Supercharged' part of your signature!
You are correct, all you need to change is the thermostat and seal.