At times it seems the engine in my Challenger is running rich, the exhaust smells of gas. The exhaust tips are also black with a soot/residue build up. The engine is a fresh build (approx 700 miles on it), takes no oil, and when warmed up runs and idles fine. When driving and I open her up the performance is good. If this is a "rich" running condition what is the best way to lean the engine out.
Thanks