I picked up a 2004.5 3500 quad cab dually on Saturday. The truck has 201,000 miles, a 6 speed tranny, and is in pretty good shape cosmetically. Well, it sounds great idling and the engine has absolutely no blow by from the oil cap or the breather hose. When you give it some throttle it makes a fuel knocking (like low octane pinging in a gas engine) and it smokes black pretty good.. Just driving at 60mph with the cruise set it puffs black smoke pretty good and seems down on power. I'm leaning towards thinking it needs injectors, but I wanted to get your opinions as well. Here are the trouble codes it's showing:

P0148
P0483
P2146
P0251
P0201
P0202

Thanks for all of your help!

 

Yes I would say injectors for sure. I had a LB7 duramax that when mine went out it would make a load clacking noise and wouldn't idle very well. Also when driving it would smoke like a freight train. I wouldn't drive it at all if that is the case cause you could do some major damage from what I understand. When mine went out I let it sit and towed it to the shop when I got the money to fix it.

 

I figured with 200k miles on it they oughtta be replaced anyways. I have a set from dieselogic on the way.

 

what size nozzles are you going with or just stock?

 

Just stockers...