Black puff of smoke at start

tyler_84c · March 7, 2014

Well that was the excuse the shop gave me as to why it was ticking like it was going to explode... I'm not even joking. I didn't think it was either.. The puffing of black smoke is not normal. I've lived in a cold climate my entire life and this is the first time Ive seen this with any vehicle

My new 2014 sierra does this in the cold -20C and colder. My work truck 2008 Ford also does this in the cold.

Yzkiley · March 8, 2014

My new 2014 sierra does this in the cold -20C and colder. My work truck 2008 Ford also does this in the cold.

Mine does it too and it's +7Celcius here in Canada. My co-workers noticed it when I was leaving work the other day and now they laugh at my truck and call it a smokerado. :>(

20L8TSierra24 · March 9, 2014

Smokerado... Lmao

pm26 · March 9, 2014

Smokerado... Lmao

A step above the Shakerado.

Crf450r420 · April 29, 2014

The direct injection motors have several injection pulses, sort of like the modern diesel motors. It also has a small pulse when the exhaust valve is open from what I have read. I don't know if this is to produce a suction for better scavenging or tor create a reversion pulse in the exhaust system. This could have something to do with it. I don't know if mine smokes on start since I can't see it normally. I guess I'll have to remember to move my mirror down to look.

Yzkiley · May 10, 2014

Just go to the back of your truck by the tail pipe and use remote start if you have it. Mine puffs black smoke on every start up no matter what temp it is outside. Hopefully my engine isn't getting full of carbon buildup. Running rich I suspect and that wouldn't be good if you're planning on keeping the truck for many years. I still like the truck and its certainly better than ford IMO as I have owned 2 in the past and never again. Maybe Dodge next time but in all reality more likely Toyota. I have had a few Taco's and they don't have many issues other than too small. By the time I'm ready for a new truck I'm sure the Thundra could be the ticket.

Kx250f · May 10, 2014

If I could post a picture I could show you the bulletin from gm saying this is NORMAL.

With the introduction of direct injection systems, gm has revised the cold start control system to reduce cold start emissions.

Quicker catalytic converter heating helps meet the ever changing emission requirements and improve fuel economy.

A dual pulse injection strategy is utilized during cold start to reduce the time required to bring the catalytic converter up to operating temps.

This split injection strategy lasts for about 60 seconds on cold start.

This process may cause the customer to see increased black smoke, soot, during cold start and should be considered normal.

There you go problem solved and you are welcome.

Pinnacle · May 10, 2014

The black smoke is "somewhat" normal. Ford is having the same problem and it arises from the fact the fuel mixture not being burned completely. In colder climates like where were from the air is thin and DI engines being sensitive to not receiving enough air so the engine will get a rich mixture. This could be a problem in terms of engine longevity. Black smoke could also be an injector issue as well.

Kx250f · May 10, 2014

The black smoke is "somewhat" normal. Ford is having the same problem and it arises from the fact the fuel mixture not being burned completely. In colder climates like where were from the air is thin and DI engines being sensitive to not receiving enough air so the engine will get a rich mixture. This could be a problem in terms of engine longevity. Black smoke could also be an injector issue as well.

Did you miss the post right above your post? It explains it all, totally normal!

Pinnacle · May 10, 2014

Did you miss the post right above your post? It explains it all, totally normal!

Are you happy with yourself now. Atleast mine has alittle more detail.

Kx250f · May 10, 2014

Are you happy with yourself now. Atleast mine has alittle more detail.

I'm always happy with myself

That's true you have more detail of everything that is not the problem, now does that make you happy with yourself....

Pinnacle · May 11, 2014

I'm always happy with myself

That's true you have more detail of everything that is not the problem, now does that make you happy with yourself....

Seems like you like yourself alittle to much as you're "liking" your own posts.

...of everything that could be the problem as applies to DI engines in general.

Kx250f · May 11, 2014

Seems like you like yourself alittle to much as you're "liking" your own posts.

...of everything that could be the problem as applies to DI engines in general.

Lol didn't know I liked my own post. I hit the check button not knowing what it did. But now I know.

2happyhicks · May 11, 2014

It was 54 out the other day and I had a rather large puff of Black smoke at start up... GM customer service.... any word on this issue? I was planning on dealing with it being a "cold weather issue" (that GM doesnt admit is there yet) well thats obviously not the case..