I have some black residue on my stock exhaust. Car is completely stock for now. Maybe it won't happen when I get my CBE.
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|2013 Audi S4|Ibis White/Black|S-Tronic P+|
|2013 370z|PearlWhite/Persimmon|Touring/Sport/Nav|F.I. CBE 18" CF|
|Sold|2011 370z|Gun Metallic|Touring/Sport/Nav|
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