Two injectors cost as much as my whole gas burner 03 truck, now I remember why I don't buy diesels.

On a more serious note as a repair shop owner we do a lot of injectors from 98+ cummins but not near as many as the isuzu and international V8s and they are way more labor to replace. I think it has to do with a lack of routine filter replacement, filter quality as well as junk fuel.

Someone with a scanner that can do more than read codes can watch the throttle reading through it's travel, my scanner will let me watch it on a graph, just slowly press it and watch for the line to go all the way up and down smoothly. I have had to replace a couple for that reason.