PeachParts Mercedes-Benz Forum - View Single Post - w108 Black Soot with water from exhaust at cold start

Diseasel300 · #5 12-02-2017, 11:19 AM

The water is condensation. Once the exhaust system warms up, it should go away. At a cold-start, the engine is going to run fairly rich (even modern cars do) to allow the engine to run decently until it's warm enough to keep the fuel vaporized and run well on its own (similar function to the choke plate on a carbureted engine). Any time you have a sweaty exhaust, you can expect some carbon to come out with it, modern cars will even do that on a cool humid day.

I wouldn't worry too much about it. Keep in mind that you'll always smell gas on the exhaust of a vehicle without a catalytic converter, it's the nature of the beast. The smell is very different from a car with a cat and a lot of people freak out about it.