Ok, first I would look at the plugs and wires. It sounds like it is missfiring with the sputtering.
The black smoke could be from the missfire or it could be from a failed fuel pressure regulator sucking raw fuel into the motor.
The bog could be fuel pressure related or a bad supercharger.
All these could be the reason but you need help from a shop that can touch it and feel the issue and give you a bid.
Friday, July 8th, 2011 AT 9:32 PM