You could just pick up/make an inexpensive fog generator. Halloween is right around the corner and most stores will have something that you could modify fer yer use. Being that it's electronically controlled, you could easily set up yer camera(s) and trigger the fog machine from inside the vehicle.
Of course, you'll probably need an inverter to hook up the machine with...but it would be a lot cheaper than trying an burning setup as the air flow could accelerate the glowing embers.