Asking about Bosch CP4 vs AC Delco CP4 fuel pump. I know some reviews say the cp4 pumps are junk. Doing some checking on what to do. I have a 2015 Duramax LML with 94K currently on the engine. I am second owner its been deleted and as far as I can tell nothing else has been changed. Wanting to understand if replacing cp4 would be a good thing and I am seeing new improved cp4 pumps. Or should I do a cp3 swap.