Al3x_666

Hello

I have an Arctic White 2017 Z06 with Borla X pipe catless & drop-in Green Air filter, when I start up my car ( cold engine ) a cloud of black smoke coming out the exhaust.
And after few minutes of driving my rear bumper is full of black particles...

Is it normal for a near bone stock car to run rich like that?

thanks

Higgs Boson

does your X-pipe have cats?

it isn't necessarily "running rich." all cars are rich at startup and cold warm up, they wouldn't run right at stoich.

the corvette is also notorious for having "dirty butt."

Al3x_666

catless x pipe but its the tiny secondary cats...

HeyDanNiceShot

Totally normal if you got the Borla Xpipe without cats.

davepl

I noticed a much larger cloud of black last time I accelerated hard. It's common to get some, but I got a lot more "junk" out of the muffler. This would all have been burned off by the secondary cats if still there?

Al3x_666

my car becomes very dirty after a few minutes of driving... it remind me my old civic 1989 when I was 16 y/o...

Im thinking to swap my borla to my OEM x pipe...

I will post some pics soon

oshvette

I have headers, no cats, corsa x-pipe, my rear bumper stays clean for about 100 miles

Al3x_666

and tune... and with a tune you probably run leaner than stock..

Warp Factor

I've never gotten black smoke on startup with any properly functioning vehicle I've owned, including those without cats (unless I accidentally flooded it). Something like a leaking fuel injector, possibly?

A little black junk on the rear of a forced-induction car is normal, since they are usually set up to run very rich under boost.

wagoetzmann

I get the "black particles" on the back of the Z, CTS-V and SRX. In fact the SRX rear wiper sounds like it is wiping sand half the time (before I clean the particles off again).

Bucknut2006

Same here. My stock C6 had it and my CTS-V and C7 when stock had those little black dots on the back bumper. The Corvettes always had it worse and I chalked it up to the flat bumper that is level with the exhaust tips.

Al3x_666

This is after a 400miles of hard driving

madrob2020

Holy S**t Batman! That can't be good! My racing yellow gets specks, but damn it doesn't run down the back! I have Borla X pipe w/o secondary cats.

Al3x_666

if you drive it like the majority of the Corvette owner... i understand why you dont have this problem 😂

Big Lebowski

Ummm. No. That would not work for me. Bone stock DSOM Z and I do not get anything like that.

Al3x_666

My dealer doesn't want to do anything because I dont have CEL.. 💩

C7/Z06 Man

Stick the stock x-pipe back on and see if that helps, without it you may have warranty issues.

383vett

What is your oil consumption?

madrob2020

Once again, someone who has no idea who he's communicating with, makes an "I know it all comment". I could be a 3 time NASCAR winner for all you know. Don't be a "douche" when someone is trying to help or just trying to lift spirits with humor (my kind anyway).

davepl

Maybe I'm confused, but:

1) Car comes with catalytic converters for removing unburned carbon
2) You removed them
3) Back of car now covered with unburned carbon
4) Dealer, fix it for me!

You removed the secondary cats, causing (or at a minimum exacerbating) this issue. You can live with it or put your cats back on, right?

Maybe I read the thread wrong, and if I did, I'm sorry, but from how I read it, this is self-induced. If you think it's more than can be reasonably accounted for by the rear cats, put the stock X-pipe back on with the cats and see where you're at. I still got some even from the factory, though.