On my 03 XK8 I had my rails and injectors sent out to injectorRx to be serviced for leaky pulsation dampeners and general maint.
On that hard rubber cross over line on the front of the fuel rails. Mine was leaking under pressure check. I was told that the rubber line has a plastic line inside it and that in my case it had cracked and was leaking under their pressure test which if I recall is more than standard pressure the system makes. He said mine was leaking and needed replaced (cost 10 bucks to fix). Mine was prob broken because I handled it as it it was just a rubber line, letting it bend more than it should have if I knew there was plastic (prob brittle at 96k miles and years of heat on it) in it.
So beware when handling that line that crosses over from one rail to the other.

 

BRG, thanks and that was one of my concerns when I did a replacement thermostat housing on a 2002, the top did not have any clearance on the crossover rail. I did realize bending it back was not a good idea and thanks to your post, I now know why.


Wayne

 

I suspect it not a rock hard plastic that is in it, must have some play in it just based on where it is. But like I said at the miles I was at I am sure it got a little hard and I did not handle it with much concern if I had known.