v8capt

I've noticed soot on the outside exhaust pipes I always drive in Sport mode. Anyone else noticed the same?

sahowley

Modshack

NPP? Those are the primary exhausts when the system is open...

Pic courtesy of Theta:

C7Joy

I have noticed this in pictures and videos of other C7s but not on my own. I am probably 50/50 between Tour/Sport.

KenHorse

Yup...

(Hint: a little bug/tar remover will clean up any of those little carbon pellets that build up. Otherwise, Windex works great if you don't want to actually polish them using Simichrome or similar...)

v8capt

I wasn't wondering how to clean them or the best polish. My question is why is there soot on the pipes. I never had this problem before on my Grand Sport. Just wondering if it is a PVC problem because of Direct engine.

Al Blue4.6l

typical on DI motors.

vettnutt

It's an exhaust pipe...yes.

Modshack

That pretty much sums it up....

9157

My car has 11k miles & is in sport 100% ...my tips are always clean....even after long trips...(500+ miles) I have noticed though, on other c7's the outside tips are always black... I figured they were not in sport! Not sure why this is ...

DriveCorvette

Not really normal with Top Tier Gas. You should check your oil and don't remove the soot. Drop by the Dealer and have the Corvette guy look at it before cleaning. I would also call Cust service and have it documented on your VIN.

KenHorse

In the NPP exhaust, when the gates are closed, gases are routed through the muffler itself where the carbon has a change to condense out within them. When the gates are open, there is no muffler involved so the carbon condenses out in the tips....

(cut open a muffler sometime and notice how much "soot" lines the interior)

SoCalC7

Are the gates ALWAYS open in sport mode? I have the engine (sound?) management setting set to "off" so my NPP always remains open regardless of the selected driving mode. I regularly get heavy soot in my 2 outside pipes as well.

KenHorse

Actually, setting it to OFF still doesn't keep them open 100% of the time. They will still close...

quick04Z06

/\ This

I had the same thing occur on my DFI Porsche.

Glen e

Clean it up, seal them and stay on it and you'll never have much of a problem - the mothers power cone is killer:

Sallye M

I always use Shell 93 octane gasoline and I still get soot on outer NPP tailpipes, even after one drive. What am I looking for when I check the oil (besides if it's at the correct level)?

ATC

+1, True on the DI Audi I have too.

9157

I have my engine sound management set to "on" . I believe they are open at start up and most local driving.. They close on the highway except when driven briskly .... I only use Shell 93.

Mr. Peabody

Welcome to the world of DIRECT INJECTION