I've got a 2003 6.0 powerstroke about a weak ago I put in a new hpop. It ran good for about 3 days and then it just died while I was driving. It started back up after a few tries. I scanned it for codes and got a u0105 ficm lost communication. When I took the truck apart for the hpop the tabs broke on the first connector at the ficm, so I figured the connector just got loose. I put some zip ties around the connector and the ficm just to hopefully get by. The truck ran fine for a little while but then just died. It would run for about a minute then die. It always started back up, usually not right away though. I hooked up a better scan tool and checked ficm stuff, volts were 48, but it wasn't always synced while cranking. It would start once it synced. Any help is greatly appreciated, I'm ready to just get this truck running good again.

 

Also i wanted to add when i was diagnosing the hpo issue i was dealing with bad batteries, i eventually replaced the batteries, but the truck did get cranked on alot with dead batteries.