hi,
this i know about as i have done a lot of these in the uk. the problem was due to early versions of the d5 injectors that because of the tight internal tolerences tended to seize "shut" and therefore the car would not start.
the cars never stopped when running but would sometimes be running fine then if turned off would not restart (although they would crank over). the fuel would bypass out the return system. the 5 injectors would ALWAYS fail as a set and must be replaced as a set, no you couldnt do this at home. most cars were done under warrenty and a car like a 02' should have been done by now. if its out of warrenty then you would have to pay, but its unlikely it would fail after 3 years if the injectors were faulty.
and lastly you can tell if the injectors are the older or newer versions by looking at the number on the injector. if you email me ALL the numbers on the injectors i can tell you approx how old.dont be too concerned these are a GREAT engine!

steve.