In recent weeks, an official from the U.S. Environmental Protection Agency (EPA) claimed publicly that, despite arguments by automakers to the contrary, tougher emissions rules wouldn't be a barrier to modern diesel engines. DaimlerChrysler recently said it would soon decide whether to test-market a diesel-powered Jeep Liberty. Automakers generally have been anxious to reintroduce diesels in the United States to boost fuel economy and reduce certain kinds of emissions, according to the Boston Globe. In light of strong sales of the Volkswagen Golf TDI and General Motors's new diesel-powered heavy-duty pickup trucks, at least some consumers appear to be ready for diesels, according to the Globe. Though diesel engines have been around since the dawn of the automotive age, only 3 percent of vehicles sold in North America are powered by diesel engines.