Let me give you a lil background on my truck, bought brand new in 03. Ran great did hardly anything to it but normal maintenance it now has 245k on it........ over time i would say in the last 100k or so it seems to be getting tired.... Truck still runs good but isnt that crisp like it once was not does it sound like it used to especially sitting next to a lower mileage 03/04. The start crank time was always almost instant now its a lil longer. nothing crazy but more like an older carb gas engine to compare......Blows some black smoke too when you homp on it as well. In its prime it would accelerate like no ones business but thats gotten lazy as well.....Fuel MPG dropped a bit but is still respectable at 21-23.........This truck has no mods done to it and had never had anything done to it except a lift pump a few K miles ago, and treatment with power service additives and fuel filters..........Im not to experienced with these engine or where to go looking for trouble.... Im in the performance gas engine business if you want big HP from BBCs im your guy...
I was thinking of pulling the injectors and cleaning them....... Back in the day i spent some time at a GMC dealer n have done my share of stuff on 6.2s n 6.5s but never touched these......Are these injectors able to be taken apart and cleaned like the GM's????? From what I understand injectors and main pump is all it could be NO ????????? Diesels are all about fuel .....I know these are quite less complex than alot of what im used to..... Just not to familiar with the systems..........
I guess what im getting at is what is serviceable and where do i start??????? Whats involved in going through a main pump has anyone ever did it????? What goes bad or gets tired in them ???? Any help Id greatly appreciate. I dont want to pay thousands for what I know I could do myself.......

Thanks

 

sorry this is long but my first guess would be the injectors, and i only say that because thats whats going out on mine and that was the problems i was having, long cranks, mileage going down, and not as crisp. but i would bring it to a local diesel shop and have them shut the injectors off one at a time while its running and see what it does, i had that done to mine and you could definately tell! (he didnt charge me ). i had replaced 2 of the worst ones because i didnt have the money for all 6 and it was just to get my by until i got back from deployment. also another thing i found is that when they go bad if you rev it up to about 2,500 rpm and mine would hang. and to the best of my knowledge you cant take them out and clean them (easily) or at all.