Mercedes Diesel Not Clean Enough

Wired News
September 6, 2006

The soon-to-be-released 2007 Mercedes-Benz E 320 Bluetec is billed as the cleanest diesel ever, but it produces too many emissions to be sold in five states.

The sedan is the first of 10 models expected to use the Bluetec common-rail direct injection engine, and the vehicles include an aftertreatment process to reduce nitrogen oxide emissions. However, that still was not enough to meet the regulations of California, New York, Maine, Massachusetts and Vermont, according to Edmunds.

The V-6 engine is powerful (400 lbs. of torque and 0-60 in 6.6 seconds) and very fuel-efficient for its class, getting an estimated 26/37 miles per gallon or going an 700 miles (wowza) on a full tank. By comparison, the Honda Accord hybrid is rated at 25/34 mpg.

The Bluetec engine was anticipated to usher in the new era of clean diesels that offer hybrid-like economy and cleanliness through the new ULSD (Ultra Low Sulfur Diesel) fuel, but not being able to be sold nationwide is a substantial setback for Mercedes and the category. If all 10 models expected from DaimlerChrysler that use the engines, including an SUV and a Jeep Grand Cherokee, can't be sold in California et al, it will take a long time for diesels to impact the U.S. passenger vehicle market.