DAMASCUS, Md. (Marketwatch) -- There is one very important thing you should know about the engine in our ML. It does not sound, look, smell or smoke like any diesel you have ever experienced. It burns ...

I refuse to go down the path of juvenile humor simply because the magic ingredient in Mercedes-Benz’s new California-legal diesels, such as the ML320 CDI, is urea -- which also happens to be the magic ...