Starting problem?

[SFD]

When I first attempt to start the truck in the morning it starts almost like gas engines do when slightly flooded with gas. I get a fairly large puff of darker smoke, the engine runs rough for a moment or two then it runs fine and starts fine the rest of the day. Any ideas? The temps are from the 30's to 50's.

[HowieE]

First thing I would check are your glow plugs. Sounds like a couple of them have gone bad and you are starting those cylinder cold and thus just passing fuel through them till the heat from compression.

Remove the wire from each plug and test the plug to groung with an omh meter. If it is bad it will show open.