6.0 running rich on diesel

I looked at a 2007 Ford 6.0 Diesel last night... It smokes a steady stream of rich smelling raw diesel smoke and never seems to clear up... Engine sounds good and runs pretty good with no miss. What do you all think?

Maybe the FICM voltage is low?

Or poor tuning.

Is the EGR system intact?

it came up with p0606. it's not coolant

p0606 is an internal failure of the PCM. not sure if that has anything to do with a tuner or not though. dumping raw fuel sounds like an injector issue

whats the best way going about testing for this?

remove lid to secondary fuel fuel, take out filter, key on til diesel gets to the edge of the bowl. disconnect wire harness on passenger side that leads down to starter... jump 12v and watch the fuel bowl for air. If its present, you have a bad copper or a nasty gunked up tip that isnt sealing. If air is present, remove one feed tube and see if it goes away

which wiring harness on the passenger side(meaning disconnect the starter?) and then check if compression is getting into the fuel system, eliminate down to the head, then pull the injectors out of that head to find the issue?

look up by the heater box.. should be a squeeze and pull connector...

ah ok thanks!