Black smoke

[seansharley]

Anyone else notice black smoke pumping out exhaust under WOT?

The sun was just coming up, the wife, and I are side by side at the light. I'm sure you all know the rest, I looked in my passengers side mirror, and noticed the smoke in her headlights, hit second gear, and the cloud got even bigger, like one of those "coal rolling" diesels

[glcbn]

I'm thinking it's a trait of the direct injection.

I always have black residue in and on the exit of my chrome tip.

[fondupot]

Anyone else notice black smoke pumping out exhaust under WOT?

The sun was just coming up, the wife, and I are side by side at the light. I'm sure you all know the rest, I looked in my passengers side mirror, and noticed the smoke in her headlights, hit second gear, and the cloud got even bigger, like one of those "coal rolling" diesels

 

It should not be anywhere near what a "rolling coal" truck looks like. But a little puff at WOT is normal. If it was truly a big dark black cloud, there's some bigger issues with your truck.

 

Not trying to scare you or anything, but if its easily reproduce-able take it to the dealer and have it checked out.

[seansharley]

Roger that, if it does it again I will have it checked out. Thanks

[SouthernSilveradoGuy85]

I'm thinking it's a trait of the direct injection.

I always have black residue in and on the exit of my chrome tip.

 

Ya it didn't take long for my 98 to get the residue. Was one of the reasons I had black tips put on my new truck, not just for looks to match my black truck lol.

 

 

Roger that, if it does it again I will have it checked out. Thanks

 

Ya I'm thinking you didn't mean it was as thick as a diesel rolling coal. All the black smoke is, rather it's gas or diesel, is just unburnt fuel so it's normal for a little black smoke at WOT, especially from a starting stop. If it's thicker or more often than it should I'm thinking your gas mileage should go down a little. If it's more often and thicker than it should be then something it causing it too run rich. I haven't noticed it in mine, but it's also the 5.3 and not the 6.2.

[Ventilator]

5.3 with 14,000 miles burning 87 octane, and no, never. My truck gets outstanding gas mileage, and I think SG85 has touched on something with the unburnt fuel.

 

I do have a hint of soot on the tip of the exhaust, but just a hint on the rim. I have never seen any black smoke, of any kind.

 

My guess is that you had the truck loaded up with gas, racing the wife from light to light, and poof, a cloud of black smoke burning off the excess.

 

Maybe I just read into your description too far???

 

What octane gas are you using? I have noticed that trying to run premium in my Camaro, it will puff a little at start-up. It was engineered to run on 87 octane, and no puffs of smoke running on it.

 

Did you just happen to fill up with a different octane level of gas within the 7 miles previous to this event? They say it takes around 7 miles for the computers to recognize any octane changes and adjust. So, if a guy switched from say 85 or 87 to say 91 or 93, it might take a few miles before it stops running a little rich??? Just throwing that out there as possibilities.

[seansharley]

Thanks for the positive feedback, yes, I had filled up with 93 before I got home the night before. The book recommends, if I remember correctly 89, or higher

[MikeNH]

GDI engines will belch black smoke when you gun it, especially if you've been driving like grandpa for a while before it. I've had dozens of rentals with GDI motors from various brands and they all do it to some extent though GM motors do seem to do it worse.

[galliher_nc]

I've never noticed mine actually blow smoke out the tailpipe, but my chrome tip has a decent amount of "soot" (if that's the correct term with a gasser) on it.