05 missing, bucking when not up to operating temp

[Doug800]

Just recently purchased an 05 superduty crew cab has around 245,000 was told it has the updated head studs and egr delete. I'm new to the sixxer so just learning. Anyways it was a rollover and cheap. But it misses and bucks if it's not up to operating temp. Like for lack of better explanation the gauge being halfway between hot n cold. It runs great at that point. But not till it gets there and If the gauge gets back toward cold starts running bad again. I don't wanna throw $ at it that isn't gonna help me out. I've done alot of research on here and am getting a good idea on how everything works on these engines but haven't came across anyone with my particular problem. I'm thinking ficm. Gonna check the volts on it today as that's how I understand u know it needs replaced. If it's under 45 volts. Am I goin in the right direction?? Thanks in advance!

[turbodiesel_02]

if the ficm is dropping voltage there's your problem and you'll need a back half.if not start looking at injectors.

[bismic1]

If it is the FICM, the best plan would be to send it to FICMrepair.com IMO. Reasonable pricing - a lot cheaper than a half-shell from the dealership,

[Doug800]

checked the ficm voltage, 48.7 volts when running. I checked the volts when it wasnt running and they were low, and the longer i held the meter on there the lower they went. Started around 6 and they were dropping. not sure if that matters or not. I assume the important part is while running. Drove it around today and it seems the longer I drive it the better it gets until I stop and either let it idle for awhile or shut it off for awhile

[bismic1]

It should ALWAYS be over 45, in fact it really should always be 47-48.

The proper way to check the FICM is with a cold engine and at cold ambient temps. Check it KOEO, cranking, and running at 2000 rpm's. ALL of these readings are important. A bad FICM can ruin injectors .............

Also - even if the voltages are good, the FICM can be bad. It is a computer, so it is more than a power supply.

[Doug800]

the only time they were low was key off. key on was over 47 as was cranking and running. Like you say< even with good voltage it could still be bad. I just dont wanna throw money at it not knowing exactly what it is. It was a rollover, so the other thing I worry is if it stayed running after it rolled. The truck was rolled in the end of oct 2011 and has sat since then. I have heard and read of may things that can affect injectors, since its cold here, 15-30f on average this time of year I wonder if I should maybe run a thinner oil, and maybe an additive? Also the MAF was horribly dirty so I cleaned tha, seemed to make the truck run better, but still has a miss to it. Also noticed if i stop on the road and let it idle, wen i first take off its good, then starts to miss, almost as if its running out of supplied fuel.

[bismic1]

Codes ?

Any way to monitor fuel pressure?

[Doug800]

Im new to these trucks< so not sure how to check the codes, other than takin it to my buddies shop and having him plug it in. Where is there a port to check fuel pressure?

[bismic1]

The port is at the base of the secondary fuel filter M12x1.5 threads

[06VT365]

Mine does the exact same thing, been doing for several months. My ficm also checked good. Put 2 bottles of Rev X additive in the oil, made it better for a while, but now it's coming back. Fairly certain it's an injector issue, maybe 1 or more injectors going south. I am planning Warren Injectors in the next month or so.....once I get some money!!!