09-15-2016,
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!