Where is the fuel rail bleeder valve on the 2011 XF 5.0?

 

That engine is a DI engine and the fuel pressure are very high and dangerously so!
I don't know any way to bleed the pressure off other than loosening a fuel pipe connection to let it bleed down.
Just be careful as the pressures are many times higher than the older style port injection engines.

Is there a reason you want to bleed it down?
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I just want to make sure there’s no air in the system. I would imagine if there were any it would exit through the injectors. I’ve recently replaced the high pressure fuel pumps and 4 injectors.

 

That's a good point and I have not heard about air problems in the fuel lines on these DI engines. It's a very common problem on older Diesels and you did have to crack the fuel lines to bleed the air out.
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