LvnTheDrm

New to my 993...so, still learning my way around. Washed her tonight, and took her for a quick spin around the neighborhood. When I came back into my driveway, and used the chamois for some touch-up drying...it came up with fairly substantial black marks when I went over the rear bumper.

Now, I just had Fister Stage III's installed last week...so, I'm wondering: Do those mufflers throw off more gunk? Or, does that carbon stuff always start accumulating right away--regardless of exhaust components? Or...is my car running too "rich" (as the 997.2's wrestled with as I understand it)?

Thoughts? Thanks--

1pcarnut

If you wipe the area with your finger is it greasy? What's your oil consumption like? Could be oil or soot or just normal combination of road grime and brake dust, it does accumulate fairly quickly. I just did a concourse event this Sunday, the site was about an hour away and my cloth came up black when I detailed the car prior to showing. All things being equal I'd say you are probably okay.

LvnTheDrm

Roger--
Not sure about "greasy"--but, if I ran my finger along the bumper, it would definitely come up with black stuff ("soot" actually seems like the right word!). Now, I am literally talking about a swing around the neighborhood--never getting out of 2nd gear, and about a mile distance...that's why I was so curious to see noticeable accumulation in such a short drive.

Oil consumption is about 3/4qt per 1,000 mi...

1pcarnut

I don't know that I've ever checked after such a short run so I don't have any further data for you, sorry. Your oil consumption is not out of line but may be adding a little to that soot. Hopefully some other will chime in, but I still think you are probably okay.

Ash

I've had this happen twice on my prior 993 - the first time, oil was dripping occasionally onto the exhaust and the soot was drafting out and ending up on the bumper. The second time it happened, I thought I might have the same issue however, I had just finished sealing up the engine all the way around. A routine inspection underneath revealed everything to be dry. My mechanic asked about my tires and suggested it could be tire dust of all things.

alcanada

I also get this black dust like particle on the rear quater panels and the rear bumper. It washes off the cloth when I wipe the car down with warm water. My ex-87 did the same thing and I thought it's common with all 911s.

Don't know what it is but would be curious to find out if others have the same issue.

CalvinC4S

Had this on all my 911's. I always thought it was tire dust.

Tania W

Yeah, I have the same issue..quite noticeable on the yellow paint. It is there even after a short drive. It's not greasy...more like dust, and wipes off easily. It's noticeable on the rear bumper from the back of the wheel arches. I figured it was either brake dust or maybe even from the tyres (that rubber has to go somewhere!)
I don't think it is anything to worry about.

Falcondrivr

it's way worse with a wing.

cp993C2S

Same on mine...it's those nice expensive Michelin Pilot Sports turning to dust.

JDHertz11

I used to get that black "dust" on the rear bumper of my 993 NA with cat bypass. I think the lack of cats added to the "dust"...

P-daddy

I think it's just your tires kicking up road dust (esp if you're in an area with infrequent rainfall). The first place they accumulate is the rear bumper/behind the rear wheels area.

cabrio993

I own a white car so I should know... black carbon sooth, burnt oils, spent rubber, and brake particles, mixed all up in the rear bumper and rear fenders. Love it!

Flying Finn

+1 and normal.

Mike W

Way worse with a turbo wing.....