Black exhaust stain

[Anonymous]

I have noticed that lately when my car has just started and is allowed to idle for a while in one spot, there is a wet spot below the tail pipe. When I look at it up close after it dries, there is a black circle of carbon. Any ideas what might be going on here?

 

[strat1960s]

The water droplets are from condensation in your exhaust system. Don't worry, this is a normal occurance. It will become less noticable as the temps rise during the summer months. As for the black carbon looking spots. A lot of the water coming out of your tailpipe is in the form of vapor. The water vapor mixes with the exhaust particles. When the water/exhaust particles hit the open air it forms water droplets and falls to the ground. If the car is left running for more than a few minutes you will wind up with a dark or black spot on the ground. I have several spots on the floor of my garage and on the freezer in my garage. With some soap and water it cleans up rather easily.
There is nothing to be too terribly worried about unless your wife gets mad about the spots.

Ted