DPF Fuel Injector1 No Response msg on dash

[Sasquatch]

OK, I understand that and will look into it , but if that were the problem, would I have trouble building air pressure while sitting and idling, or does that indicate that I have a hole in an airline somewhere near this same area?? , have tackled many problems and solved them over the last year since buying this used truck, but this is a bit of a different situation for me, I am fairly new to the dpf stuff.it's just odd to me that I hear such a steady loud hiss sound. Thanks again.