^ which is nearly impossible to do, and will be a lot of headaches for the owner. And that doesn't guarantee the car will be fixed, and your warranty doesnt get extended.
As to my consumption, its burned 1.75 quarts in 4200 miles during the last couple months of "winter".
The soot, yeah its pretty thick. I wash my car every week and pressure wash it (gently) after work on fridays. The back of the car is the only part that has black buildup. The rest of the car has light colored dust from the nearby limerock plant.