2003 diesel model, it does not start

Hello people, I introduce myself, my name is Nicolas and with my old man we have a 2003 Diesel engine that we use it for the work The subject is that this morning I do not start! And we get to despair. He told me that the problem could become a valve that makes the diesel not work or something. This afternoon I try to make it work and adjust a screw and nothing
I would like to ask if anyone knows what can be, the engine is FQ8

It is supposed to have strength and that the starter is fine, is it injecting diesel? The safest thing is that you have some bad sensor, example of the motor steering wheel, try to try with the spare key ...

Is Cammon Rail or Normal Petroleum? That is, do you have electronic or mechanical injectors?