3.0 Duramax cranks but won’t start

[V8Chevy]

15 hours ago, WontStart said:

I am scenario #2

 

My dealership has ordered my truck a new ECM over a month ago. However, they are on National back order with no ETA

 

Man, sorry to hear that.  It's ridiculous for them to make you wait.  Unless it is a widespread problem, it seems like they could pull you an ECM from the factory production line since a portion of the production units aren't necessarily sold vehicles and are just going to sit on a dealer's lot for some duration.  Taking care of your issue should be top priority, since you are a paid customer.  There's no excuse for you to have to wait for a back ordered item.