2010 Pete 389 ISX 871 shuts down intermittently

[Billcummins6]

I have a 2010 Pete 389 with a ISX 871 that will just shut down on me. Under power and at an idle. It’s like turning the key off. It will throw a code of “fuel delivery pressure low”. I spun filters and no go so we changed the engine wiring harness. I took off this morning and 15 minutes down the road it did the same. I can restart it when the code goes inactive. Sometimes it will run seconds other times it’ll run hours. Any ideas? They are telling me now to change the ECM ,which is a shitshow because it’s demandated. Any ideas. I do have access to a shop and a laptop..
Thanks in advance,
Bill