Single Status Update
Thanks Joe. I've proved the pump is faulty using a separate 12v supply.
The worst of it is that nobody seems to know which pump it is. It's not the same as all the other xj8's. this one has an integrated fuel sender. All the others have separate senders which fit in the center of the tank. My tank is completely different, both sender and pump are inside the same assembly. A very experienced mechanic told me he had never seen this on any other xj8.