Black smoke what is this?

[Dsm4lyfe12]

Stupid question but,

Its a dark type charcoal smoke that comes out only while im in wot.
Perfect compression, but will valve seals cause this?
I was watching two step videos on youtube and noticed most cars smoke just like mine, should i worry?

 

[DSMReviver]

When i see this in the past, its because the oil ring/scraper is worn and letting oil past the piston where it get burns up in the chamber.

It will not show up in the compression test if this is the case because your compression rings are still in good shape.

Or another speculation is that you are running rich in WOT. you could get a good tune and a gauge should solve this problem.

 

[Dsm4lyfe12]

Yeah, im running stock boost. Typically, i heard that our cars run rich from the factory. But imo, these are brand new rings and bearings. Its not pouring out smoke, just a puff at wot.

 

[And_44]

Blue smoke is oil, white smoke is coolant/moisture, and black is fuel.

And having it at WOT your ecu is dumping alot of fuel. Check for intake leaks, make sure ignition system is maintained and test your o2 sensor. I know romping on it and in WOT alot of cars will throw out a black cloud.

 

[Dsm4lyfe12]

Im guessing its my o2, its old. And the 02 housing is stripped...

 

[DSMReviver]

Yeah, im running stock boost. Typically, i heard that our cars run rich from the factory. But imo, these are brand new rings and bearings. Its not pouring out smoke, just a puff at wot.

Do you have any wideband of some sort to monitor your air fuel ratio?

 

[And_44]

Yea, finding a used o2 housing should be easy see them al over b/c peeps upgrade the stock ones. And an o2 sensor for a plug a plag factory plug is like 60-80 bucks from auto parts store. The universals may be cheaper but I'd spend the extra so i wouldn't have to mess with a wire hack job.

 

[icemanracing]

big question everyone forgot to ask is what kind of exhaust do you have.
Are you runnning a Cat still?

 

[And_44]

Even without a cat you shouldnt have a huge plume of black smoke. More then with a cat but not to much.