hard starting cold or hot

[c6j12r]

im new to this forum and i am looking at a 1995 gmc 3/4 6.5 turbo pickup. the truck runs great once it starts. it will crank for 10-15 seconds and finally start and it the engine gets real loud and then gets back to the normal rattle and then the truck runs great. it does this weather the engine is cold or hot. i hooked it up to a scan tool and it tells me
ignition control
camshaft sensor
circuit problem

any ideas where to start? i am new to the 6.5 turbo diesels. thanks in advance

[c6j12r]

i forgot to mention that the check engine light is on.

[c6j12r]

one other thing i should add is that sometimes it seems like the truck has lots of power and then sometimes it seems doggy.

[Bnave95]

Deal with the crank shaft sencer first. This happened on my 95.