Black smoke out the tail pipe is a sign of burning way too much fuel, not oil. Not sure what kind of chemical is going to overcome a mechanical problem but it doesn't sound like that's what you have. Now the engine may be getting overloaded by fumes being drawn out of the crankcase and being burned as fuel in the engine. I suspect you have a sensor problem causing too much fuel to go into the engine but you might want to wait until all the stuff in the oil vaporizes and is gone.
You can check for diagnostic fault codes too but the MAP sensor has the biggest say in how much fuel goes into the engine, and while it can report the wrong manifold vacuum leading to this problem, it will not set a code unless the signal voltage goes beyond 0.5 or 4.5 volts. It can be wrong but still within that range, thus setting no code.
Aug 16, 2012 at 4:13 AM
