Dark colored exhaust is usually a rich condition. Oil consumption is usually indicated by a bluish white exhaust. The unburnt fuel smell and carbon out the tail pipe indicates carburetor issues as well. I would look at the carb before jumping through too many hoops chasing my tail.
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.
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