I have been reading threads about similar problems but mine is a little different I don't have a rough start. The first time I go out to start my truck no matter what time of day or if its 110 outside it starts fine but idles a little rough and if you drive it it sputters an shifts hard till the oil temp comes up im running sct live wire but even when vehicle is detuned and programmer is off conditions are the same an also no codes what so ever truck has 72,xxx miles any suggestions?

 

Hmm, first I would check ficm voltage. Should be 48v, next I would check fuel pressure. Should be above 50psi. It sounds to me like either low ficm voltage or weak injectors. What oil are you running. I use John Deere 0-40 synthetic in all of mine and they love it. If your spool valves in the top of your injectors are sticky from thick dirty oil they get weak on power and randomly spit n sputter until the oil gets warm and thinner then they'll loosen up. Worst part is I have seen quite a few people melt pistons outta these engines when the injectors start acting up!!

 

I run rotella 15-40 I'm gonna check the voltage

 

ok so I just realize my sct livewire reads my ficm voltage an with key off its reading 11 v running t reads lie 13 I cant say I remember what t runs when its up to temp do you think it reading correctly

 

I cannot say for sure if it is reading correctly. I have personally never used a SCT tuner to check for FICM voltage. But if I had to take a guess id say its reading correctly and your FICM power board is bad You don't have to buy a whole new $700 FICM you can go down to your local auto parts store or online a buy a replacement DORMAN FICM power board for somewhere around $150. You have to remove the FICM, take it apart and install the new one. Doesn't take anything more than a couple torques screwdrivers and about 1 hour of your time to do so. Also I am a FIRM believer in 15w40 rotella its the best oil on the planet IMO I run it in EVERYTHING!! BUT, you will notice much better operation and drivability with a thinner full synthetic oil in your 6.0PSD. I would recommend changing FICM power board and changing to a thinner synthetic oil. Hope this helps and good luck!

 

i agree with the ficm if you havent done so already. mine would do the same (start fine, idle a little rough and run rough until warmed up) until one day no start. ficm tested acceptable until the day it died. i sent ine to all computer resources to get rebuilt. turned out both the voltage and logic side of mine died. just my 2 cents, i run 5w40 rotella t6 and the trucks runs silky smooth.