Can anyone help with diagnosis of this fault code 4560 fuel rail pressure I believe? for my sons 318d 2006, when he's driving it the management light domes on it breaks down then restarts after a couple of minutes

My dads car (hyundai Santa fe) did a very similar thing, engine light came on then engine cut out leave it 30 secs and it would start again and be fine for about 3 miles and then do the same again. Turned out it was a injector seal had gone and as pressure built up opened the seal and then lost pressure on that cylinder.

Turned out to be low pressure due to blocked fuel filter

Result !!!

the attached link has all of the BMW OBD codes, including yours

http://realitypod.com/2012/06/bmw-complete-diagnostic-fault-code-list-e36-e46-e90-and-more/