I've got that problem on my 4.2 SV8 where the crappy plastic plug on the vacuum line to the intake elbow failed and the hose wobbles about and is basically falling out. The car has been off the road for about 6 months whilst, in between the relentless bouts of rain and work, I've been battling to get the bugger off the back of the supercharger.

Finally I've managed to get it off, but whilst fiddling around inside the engine bay I found a few places where some seals have failed, so I've also got the RH cam cover, the coolant thermostat connection to the engine and the supercharger off.

From where I am now replacing the intake manifold seals seems like it would be straight forward as all the bolts are now exposed. My question is whether I should replace them "since I'm here" or should I leave well alone as disturbing them might create more agro than its worth?

Also the EGR seems a bit "sticky", is there a way to bench test if it's working properly before I try and reassemble the engine?

I might also post this to the XKR forum, since it's basically the same engine and there's hardly any XF SV8's around.

 

Don't forget the hose under the SC. That is a big job to do and you already have the SC off so you have done most of the work already.
At this late date I would consider changing ALL the coolant hoses and there is a bunch. I think my old 2005 S Type R has 23 hoses in total.
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Yea, I replaced all the coolant and oil hoses about 2 years ago when I changed the SC pulley. When that was taken off you could see they were all getting brittle and a few of the oil lines had tiny leaks. Shame I didn't think to check the elbow joint at the time, would have saved a lot of pain