My 04 is just shy of 100,000 and not chipped. I don't think I've ever seen smoke. Today I got stuck behind a slow vehicle and stepped on it to pass. The truck was not quite warm yet and in my mirror I saw a small cloud of gray smoke. A the next light I tried stomping it again and no smoke.

What does smoke mean? Anything to check? Anything to expect to fail?

I have a better tow vehicle now so my Cummins doesn't need to work much. I still love the truck though and hope to keep it a few hundred thousand more. So at this point I'm all about maintenance.

 

These things will smoke a little bit stock, especially if they are not completely warm.

Black = burning lots o' diesel
blue = burning oil
white = head gasket or injector

The biggest things for a common rail is regular oil changes and clean fuel (preferrably 2 micron filtered)

 

Not uncommon for a diesel to put out a puff of smoke when you get down on it. It just means theres some raw fuel that didn't get burned completely. If you notice, most diesel 18 wheelers will put out a belch of smoke when they accelerate. Then the smoke disperses and is hardly noticeable. If real black it's a lot of raw fuel and you may have an injector leaking. If white, you may have a more serious problem.

 

Yes I've seen diesels smoke. What I'm wondering is why mine never did and now it's begun. Also, why once and not again. Something changed. Hopefully it's not an expensive change...

 

You said it was not warmed up, more then likely the combustion temp was alittle low and that resulted in the gray smoke, the next time you tried the engine was warm and there for you got a complete burn and no smoke.

 

if it was pretty cold out its common for them to give out white smoke

 

i agree with black means lots of fuel and so on. i was told that gray means its burning crisp. like its doing good.

 

grey or white can be unburned fuel, especially if cold. Do not jump on a cold diesel. Use part load to warm it up then good to go.

 

If the weather's cold and I've been idling mine a bit and putzing around town, it will let out a puff of smoke if I get on it hard. It just seems to clear out some soot that's been building up, then it's fine.

 

If sun behind you black smoke looks oil grey in mirror. Check when sun in in your face. It'll probably be fine.

 

My 5.9 would do that stock it I drove it easy and then romped on it. The soot builds up on the walls of the exhaust and in the muffler.

 

Yeah, I have noticed that. Drive around easy for a week, then romp it. Holy cow it can belch a big cloud.

 

Exactly. Perfectly normal.