just for an update i pulled the codes because it killed again on me. Here is a copy and paste of my previous post.
Ok well for the first 100k miles i had my 6.0 i always defended it because i had 104k trouble free miles. Since then however its been one a flat bed 4 times.
Just for a little history i replaced the egr cool and oil cooler at 104k.
Had sluggish throttle response and eventually a no start that was fixed simply by wiggling the icp sensor plug.
This newest issue started one morning when on the way to work it started acting weird and eventually died. Found out it was a bad alternator, threw a new one on and everything was grand. Until a couple days later when while i was in traffic as it was going back down to an idle it decided to die. Tried to restart and it wouldn't fire, turned over fine but wouldn't light off. Well about 15 minutes later after i had called a tow truck curiously i tried to fire it up again and it fired right up. Killed it and started it a bunch of times to check and ended up driving it home and then for several weeks with no issue. I did pull the codes and it had an FICM low voltage code. Well everything seemed to be ok, other than the fact that it always runs like crap when i first start it, has trouble gaining rpms or getting up to highway speeds until its at operating temp but its been doing that forever. BTW when i pulled the codes ficm voltage at idle koeo was 46v. Well it ended up doing it to me again today killed while i was driving it and wouldn't restart. Luckily i was right by home depot so i went in there for a little while blew about 15 minutes came out fired it up and drove it home without an issue.
So is it just an FICM issue or could it be something else?
So before i drop the cash on a new ficm whats everyone's thoughts on the 1378? Could it be something else since that's a supply issue? I did just put a new(autozone) alternator on and it seems to always kill at idle or close to it. Is it common to set both codes when the ficm is bad? Just wanna make sure i spend good money this time around.