One of the more challenging things I found cleaning the car, was getting rid of the black carbon on the tail pipe. I've tried strong polish, steel polish, and even hot boiling water to try and soften the carbon but to no avail. Last weekend I got creative. Saw an old man cleaning his dirty pot with scour pads. Went home and tried it. I have to say the technique is so simple. All you need is 1 scour pad (go into your kitchen I'm sure you'll find some). Next dip the pad in your car shampoo. Scrub the tail pipe. Voila, no more black carbon stains.
Btw, why is the tail pipe always carbonised? A mechanic told me that the fuel mixture is not balanced. Too much petrol in the combustion. BMW? any answers?