As diesel runs on air and fuel, so it's got to be one or the other. There is no "ignition" to fail.
How do you know fuel is reaching the injector pump? And that the pump is injecting? Try disconecting the fuel line after the primary filter and see if fuel spurts out when the key is turned on. That will verify that the lift pump is moving fuel toward the engine. Then again after the secondary filter, to make sure that's ok. What about the air filter? Could it be clogged?
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL