I went and had a look at a '95 3500 with 112K miles 4x4 auto. Nice truck, BUT it has a serious issue.
Granted the batt's were both dead, one ground cable was loose, and it was 30* (nuthin for a good cummins)
Symptoms:
*But it will start missing and blowing lots of blue smoke above 1500 RPM on a free idle. *If you rev on it, it huffs even more blue smoke, and pops n farts, n bucks, n seems like it runs out of fuel. (will it run with a bad lift pump like the 1st gen?)
*Once the RPMs drop back down under 1500 it misses for a second maybe 2 then cleans up.
*Cold it huffs a lil more blue smoke then it should, and has a slight miss, till it warms up a bit. Once warm, the blue is gone, till u rev it over 1500 where it misses.
*Warm there is no idleing miss till 1500.

The blue smoke smells clearly of unburnt fuel, not oil or antifreeze. Now it does look clearly to have been beaten on, not so much body wise, but just the overall appearance and whats been done for modifications, NOT to the motor. However the timing cover has been off obviously. KDP?

I thought burnt piston or a hole in a piston, but it idles nice when warm. It hasent been listed for sale yet its out back of the dealers garage. I guess the buyer backed out when they saw it. Hmmm go figure.

Whats been checked and asked:
*Supposivly they drove it and it drove fine 3 weeks ago.
*The oil is clean and smells like oil, though the Napa oil filter isnt so clean.
*Its slingin oil from the timing cover, (crappy blue RTV job?)

The dealer says 9-9500 fixed, ABS light, Brake light, 4x4 light, airbag light, reupholstered driver seat and center glove box top, headliner, and front bumper replaced. Not a bad deal for the miles and what all has been done to it I dont think. BUT heres the kicker, he'll wheel n deal with me if I take it as is. The motor acting up is working in my favor big time, I would have the airbag light fixed before i took it, and I know what the problem is with the ABS light.

I just wanna know whats wrong with the motor, and if u can offer some guidance on the 4x4 light that would be nice, It was in 2wheel drive i shifted the t-case into and out of 4high. Thanks guys! I know its a long post.

 

Well my first guess would be timing. I'd try to find out why the cover was off, if they where in there replacing stuff they might have gotten the timing off. It'd have to be really retarded (timing wise) to be as bad as you describe. Next would be injectors needing to be rebuilt/shimmed upto the correct pop-off PSIs.

The 4x4 problems are probably vaccum related as one of the lines may have a hole in it. Could also be switched around if somebody was under there messing with it.

 

Hmmm... thanks for the info. I cant immagine the injectors would be that bad, its only got 112K on the ticker, but i spose that could be wrong. It doesnt huff any white smoke thats what bugs me bout timing. I hada guy on CompD suggest it could be the KDP fell n knocked out the timing. The Cover has been off, n it is still slingin oil. Hmmm........ baffling.

The last rig I know that did something similar was a 1st gen with a destroyed IP internal shaft.

 

You go straight for the expensive stuff ............check the cheap/easy to fix stuff first.

I pulled my stock sticks at 185k or so and they were pretty bad. Popped at like 220 bar or around there. Suppose to be up around 250.

I'd bet it has something to do with fuel delivery. Wether it's timing, a messed up injector(s), or something in the pump. All are just excuses to go bigger.

 

My thoughts EXACTLY! Thats all what im thinking, it has to be simple, Timing was my initial thought, (still could be) but the lack of white smoke (but could be covered up by blue?) kind of has me pointed elsewhere. The fact it has to recover for a second or 2 has me thinking injectors, or dying LP.

Another thing I should have pointed out, once warm, I can make it idle at almost 2K before it starts its crap, floor it at this point and it will rev 3 maybe 4 hundred more then act like its running out of fuel, but still blow lots of blue, fart, crack, pop, whatever u wanna call it, drop the RPMs, it recovers a second later.

So how do I test some of these things on the dealers lot, so I know it isnt a 2K fix once I buy it as is?? Id buy it as is for like 6K tops and save a few grand by fixin it myself. Its just to clean and modified to offer any less in my personal opinion.

 

Not much you can do w/o tearing into it alil.

Any bosch, cummins, or diesel perf. shops in the area? Or some shop that could give a 2nd opinion. In this case I think it'd be a wise move even if it costs alil $. That way ya know what your getting into.

 

Timing. Those symptoms are nothing but a retarded timing issue. If you can get it cheap enough, it is easy to set.

 

I have one shop in the general vacinity, and they have gone to $*it. I do have a second opinion though. Despite the folks that have been helping me out on the forums. Apparently my buds, bud had the exact same thing happeneing to his early 2nd gen, swapped out injectors for some 370 marines, bam, fixed.

And thanks for your input MnTom. I am going to see just how "cheeply" I can get this thing, I have a few proposals for the dealer. I need to find some steel wheels and tires, and tell em i have narrowed it down to injectors.

I hate the front wheels, aluminum single wheel. Well ok, i dont HATE em, but they aint for me. I think a set of 265-85's would look right nice on a lifted dually.

 

its probably timing, that would be my first guess

 

im going with timing also cuz thats what every one elese is saying