Hard start
 

Hard starting,no smoke unless I give it some throttle. Seems normal amount of smoke,but when I shut it down it's back to hard starting again.Regulator stuck,or bad injectors?

If you're speaking of a hard start problem when it's been sitting over night or when it's cold it sounds like you might have a problem with the grid heater.

Use a continuity tester (ohm meter) and check continuity on the grid heater that's located at the base of the intake horn. Be sure to disconnect the wires on it first.

If the meter reads that it has resistance it's good. If there's no reading it's bad.

If it checks out you have a problem somewhere else in the fuel system.

How many miles are on the injectors?

How many miles on the truck? Is there a fuel leak at all where air can be getting into the fuel system? Do you have a way of verifying Rail pressure during start up?

Well I had injectors tested,4 we're bad. Replaced them with re,man's. My truck starts like a champ now like it should but,my mpg is down 3-4 and smokes lightly but constantly going down the road. I think maybe one of them is stuck. Tried two tanks with cleaner, no difference. Anyone have any suggestions? *note,injectors came from a certified bosh dealer.