05 6.0 F250. It's been running rough for a while, and last week, it took a bad turn for the worse. Very hard to start, sounds horrible, no power. The local diesel shop said it was a bad FICM. The voltages are good though (47.5-49 at KOEO, cranking, idle and high power). Tested the alternator and batteries; all 3 were bad and have been replaced. I found the exterior plug for injector 8 was loose and reattached it. That made it slightly easier to start, but not a real fix.
I'm getting codes for P0265, P0268, P0274 and P0283 (circuit high, 2, 3, 5, and 8). Can the FICM be still bad if the voltage is good?
Could be possible but the 235 kinda tells me that you should check your FICM connections and make sure they are all secure and snapped. Also could have chaffing either on the ficm harness or injector harness. Heck the pins to make sure none are pushed in or bent. This would be my first course of action.
2006 F350 4X4 CAB CHASSIS w/ Truck Bed
Blue Spring, Mishimoto tstat
I tested the continuity from the middle connector out, through the injector coils and back to the other pin on the connector. I got 1.0 - 1.1 ohms for all 8 (open and close on 2, 3 ,5 and 8), so I don't think it's the harness or connector. I'm guessing something on the logic board of the FICM failed. Sending it in to Ed.
Got a new FICM from ficmrepair.com (logic board and power boards were both bad. Got the atlas 40 tune), and got an injector 2 high circuit. Replaced it and it's running like a top. Went from 13.5 mpg to 18.5.