Some moron said: "Um dont a lot of those heaters emit carbon monoxide. I've heard of too many people dying from using heaters in cars and tents, dying from carbon monoxide."
Is everyone around here really this stupid? He said get an ELECTRIC HEATER. An electric heater doesn't give off carbon monoxide, only a heater with a flame will produce it. Yes, you could die if you let your car's engine run all night, with your windows closed up, and you have a bad exhaust leak, but if this was a common problem there would be a lot of dead truckers, cops and cab drivers out there.Regardless, you don't want to let your car run for heat all night, just to be safe, but if you have a zero degree bag you should be fine.