[ducmon]

It sounds like you may have this problem.

Locked Out of My Fuel Tank

Today I tried to put diesel in my car, but the silvery metal door, behind the yellow diesel cap, refused to move. I asked a mechanic at the gas station's body shop to come out and take a look to be sure that it wasn't me ;-) He could not get the nozzle to go in either, and asked his mechanic...

www.fpaceforum.com

 

[ducmon]

From what I understood from the other thread. They said something had become loose and it jammed the flap.

You may have to dismantle the flap.
It seems to be part of the cap.

Blocked fuel tank breather/vent

I can't fill the tank on my 163 PS diesel. I'm pretty sure the breather is blocked. The misfuelling protector has not dropped down so it's not that. Does anyone know the layout and position of the breather(s)?

www.xeforums.co.uk

There are pictures from Topix with a description in the thread.

 

[ducmon]

I would start by removing the the surround and looking to see if there is any thing has caused the problem.

As it not your car though it may be better to suggest that he goes to an independent jaguar specialist