i recently bought a 2004 connect 1.8tdci

after a week of pottering around all being fine, i took it on a job witch included a motor way stretch.
after around 15 miles the glow plug light started to flash and the engine cut out. after a couple of minutes on the hard shoulder i tried to start the van and all was well for another few miles. after eventually getting to the job i realise that, The van only does it when the engine is at running temperature and when you hit a slighty uphill. I had the van plugged in at my local garage and it came back as a fuel pressure sensor. Can anyone please shed some light on this problem as i have had a number of suggestions but none that are certain to cure it. I have listed the suggestions below from the garage it was plugged in.

fuel rack
fuel pump
fuel filter
one or all of the injectors

I am in need of some direction as money is tight at the min and dont want to spend the money on the wrong thing

thanks