Aa few months ago, Jag v8 helped me solve a years long lean code problem that turned out to be a hole in the air tube between maf and throttle body. Once I sealed that up, I instantly got rid of code and was able to smog the car. Alas, the leans are back and I reinspected the air tube but it seems fine. I know all the reasons for lean codes and I have fought them for years with this car (2005 3.0 s type). I'm going to try easy fixes first such as getting a new mafs (which one please?) and I would like to rule out the evap part pictured. What is that part called, and where do I get one?

 

I replaced mine a couple of years back. I believe it is called an evap purge valve. It comes as an assembly with the bracket, solenoid valve, and canister as a unit. I bought an authentic Jaguar part off eBay for just over $100. Look for and download the Electronic Parts Catalog or EPC somewhere here in the forums. Super handy, it will help you search with the right Jaguar part numbers.

 

Here is an item that matches your picture's "1X43-9S446-BB," "153400-0290" and 'Denso 029" from UK. It is indeed a purge valve solenoid.

eBay UK X-Type Purge Valve

 

WTG JagV8!!!

 

Here is a link to the part, with drawing and part number:

https://www.jaguarclassicparts.com/uk/part/XR849660