need help

[wolverine]

i have a 2011 t-660 kw w/450 isx cummins no def! red engine light comes on while driving and sometimes while idiling! but never shut the tk down been going on for about a month now! my yellow check engine is on and display crankcase pressure. i changed the sensor and filter still on! had new egr.dpf filter and catalyst installed. the tk dont have def fluid!

[Rawze]

Sounds like it could be a wiring issue with the crank case filter sensor, or an excess blow-by issue.

Have you done any kind of tune-up work to it?
Performed an EGR tune-up?
replaced any sensors for the EGR?
How much oil does the engine use?
miles on engine?