Due to seasonal allergies, I decided to do field day mobile in class 1C in order to have a controlled environment.  Toyota assured me that idling my Avalon would not harm it.  I used 8 gallons of fuel for a 25 hour idle.  I placed a carbon monoxide detecter in the back seat just to be safe.  I missed the social aspects of doing fiel day with my club, W0DK, but the comfort was worth it, and the contest was fun.