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Black smoke , rough idle high RPM on 1990 BMW 325i

Rookie cbe0621eac06868b3efe0d8d1d3611e23c60d3114864ea2ec19a68cfbd3eebab
My car idles rough and black smoke with high RPM .Its a stick shift so it BUCKS at will due to bad RPM.
(1) Answer
This is indicating a rich running engine. Check the fuel mixture and fuel pressure, make sure they are within spec and resolve accordingly.