FICM voltage question

[brianjbeach85]

Pretty sure i know the answer to this, but looking for input on it none the less.

FICM V is showing 47.5 .. i know it's supposed to be 48 constant regardless of starting.. running.. or pre starting the engine. When i crank it up it can drop to 46-47.5 range but after initial cranking and it turns over its back at the 47.5. How much dmg if any am i doing to the injectors? Cranking doesn't last more than 5 seconds till it fires up so i still feel like i'm good as far as that goes

If im not doing dmg.. at what point do you say F it at buy a new power source side? i've heard 45V is the magic number to replace it for sure.. is this true?

As for replacements i am going with the BPD 6 phase FICM upgrade for reliability and redundancy. i've started saving since i've noticed this issue.

[RRF985]

IMO you're fine for now and your injectors are not being damaged. Mine is running the exact same as yours. I have seen mine hit 44V on a cold morning (32*f) for a few seconds. 45V is supposedly the replacement voltage or where you should start thinking about replacing. I too am looking at doing the BPD but I can't decide whether or not it's worth the extra $200 for the 6-phase over the 4-phase.

[Fishermedic]

47V+ is within spec and not hurting anything. Below 47 I'd start paying attention and when it starts dipping to 45-46 get rid of it, even if it is only for a few seconds on a cold day (after load testing the batteries and checking alternator of course). It will only get worse and it will damage your injectors, FICM's don't fix themselves!

My old FICM started dipping to 46ish starting when it was cold out. Over a few weeks it started falling lower and staying low longer and longer after the truck was running. Went with ficmrepair.com and I was good to go, 47.5-48 all the time.

My BPD unit runs at 47.5 to 48 ALL THE TIME, cold, hot, wet, dry, night or day. I have the insight alarm set at 47.2 and it has yet to go off.