How hard/expensive is it likely to be to get a ten-year-old Jeep to pass California emissions standards? [more inside]
posted by fuzzbean on Oct 19, 2006 - 8 answers

Why is biofuel diesel, instead of standard gasoline? [more inside]
posted by yesno on Jul 7, 2006 - 16 answers

What are the most efficient cars readily available in the United States? Mileage, fuel & emissions and size are all important criteria.
posted by luriete on Apr 12, 2005 - 27 answers

I love my car, but am becoming increasingly concerned about gas mileage and environmental responsibility. It isn't a guzzler, but I know I could do better. What are your experiences with diesel cars? [more inside]
posted by odinsdream on Mar 17, 2005 - 11 answers