Living here in Michigan, as the temps start to drop, I've noticed that on a cold start up (after truck has sit for 6 or more hours) I get some white smoke. It doesn't happen immediately after start-up, but maybe like 10 sec later and then will smoke for 30sec. - 1 min. then stop. Is this normal and why does it happen?

 

I have that happening too. The white smoke is simply unburnt diesel. The reason that it happens very shortly after startup and not immediately and then goes away, is that diesel is burnt under temp/pressure. At startup the there is a preheating that is done and cylinder temperatures are higher than a few seconds after startup. The temperture then raises and the white disappears. There is a TSB out I think it is TSB 18-037-04 that comments on a fix for this partially. Hope this helps a little.

 

The flash did not help with my start up smoke however I did gain like 2 mpg.

 

I had the latest TSB done a few weeks ago. Started to notice the smoke after. I don't have anything to compair to before because fall temps have just started to roll in.

 

How much do you have? Before the TSB on a cold morning it would be like a fog rolling over my truck. Now there is none unless I look back there in the mirror..even then there isn't much.

 

White smoke = Boiling tires

 

This is what I've noticed also, as I have the same situation. I believe the white smoke at start up with a cold engine is being caused by the cat not being up to temp to burn the diesel smoke completely. I've noticed my truck steams like a gasser until it's warmed up a bit now that it's getting colder.

 

I have asked this question to others before and everyone states that it is unburned diesel fuel, but in my mind it simply doesn't make sense. Unburned fuel is black smoke, not white. White smoke, if it lingers around is anti-freese(ethelene glycol) or water vapor. Usually smell can identify the difference. White/blue smoke is lube oil. Now, back to the original question. I think the white smoke people are observing is a thermal issue caused by late injector timing creating water condensation in the exhaust. This condition goes away once the engine temperature rises and the dew point is no longer being crossed by the air mass. Futhermore, the TSB that seems to help this probably advances the injector timing a bit because it also seems to help mileage. Now, if I have this wrong, I hope somebody straigtens me out.

 

partially burned diesel is black the hydrogen was burned but the carbon was not white smoke is fully atomized completly unburned diesel more likely your seeing "smoke" that is actually water vapor caused by the heat of the exhaust system like on gasoline powered vechiles like a con trail on planes.

 

Not much. I only see the smoke while driving off to work in the morning in the mirror. This only lasts for about 30 seconds. If I give the pedal a quick push, there is a good amount of white smoke, then it's gone. If it's sittin in the driveway then you hardly see if cummin out of the pipe.

 

Injectors. Replaced 'em,..now no smoke.

 

Hey OUT OF HERE did the dealer give you the same sob story about those cab plugs ?? I spoke with DC customer service and he told me to purchase them and they will reimburse me . Dealers are supposed to install them after transport he told me . Oh well was nice meeting a fellow member and sharp ride you got there .

 

Yes,...likewise nice meeting you and seeing your nice ride. It was a wasted trip for me however in that they said I showed to have the latest downloads so they are saying I have 18-037-04 already. I just don't understand when My truck was in on 9/22 and it wasn't released till 9/27 per what Cummins told me. Either the guy at Cummins was wrong or two DC dealers are full of it. I suspect Cummins had it wrong at this point, but it still wasted a bunch of time for me. I'm not gonna make it to Mustang Muscle for the dyno pull,...family stuff. And yes, they gave me the same BS as you on the plugs for the cab. Later

 

White smoke is unburned hydrocarbons. Combustion did take place, but not at a sufficient temperature to burn all of the hydrocarbons to Carbon Monoxide and water.

It can also be condensation as suggested earlier. There is a difference, but its hard to tell. Condensation tends to dissipate into the air faster, where white smoke with "hang" in the air for awhile before dissipating.

It can be addressed with calibration adjustments (which is part of the TSB).
The service calibration was optimized for fuel economy, as FE is the biggest complaint now on the 600/610 trucks.

 

Did you ever see a set of fuel injectors undergoing a pop and atomization test? What color are the fuel plumes coming out of the injectors?

Rusty