07.5 6.7 with EGR and cat delete. I'm having an issue during idle and under load. Originally the problem was mild to moderate "sputtering" at about 2000 rpm under load (acceleration, hill, towing). Now, it sputters at idle and throughout the power range, regardless of being under load. Problem started before deletes so not necessarily related. Fuel filter is new and I haven't been getting fuel from a new source. 140k miles.