Is it better for the environment to drive or fly a long distance? [more inside]
posted by JPDD on Oct 12, 2007 - 16 answers

What car models are best for biodiesel? Anyone done the full conversion to vegetable oil? [more inside]
posted by jruckman on Feb 8, 2007 - 16 answers

Does anyone have opinions about Terra Pass? [more inside]
posted by of strange foe on Nov 16, 2006 - 4 answers

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

LPGFilter: No, I don't want to filter out LPG, I am considering getting an LPG conversion for my car... [more inside]
posted by gaby on Sep 10, 2005 - 15 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