A fond memory of my youth was watching my father's ritual of starting the BBQ with a can of gasoline and farmer's matches - woof!
What can I expect from someone use to heating up his rations with a bit of C4. ;-)
Don’t waste a perfectly good flare!
Wrap a small rag onto a stick, then dampen it with gas, kerosene, or diesel. Hold it next to one of the vehicle’s battery cables, and use a long screw driver, wrench, or spread-open pliers to spark it alight. If nothing else, you can connect a set of jumper cables*, and use the free-end clamps to create the sparks.
You can use it as a torch, if you modify it a bit to make it burn slower & longer; or use it as a match, same as the flare is use.
*In a pinch, battery cables can be used for crude emergency light duty welding, using 16d nails or bailing wire for ‘welding rods’.