When Ted gets into the disabled red van, the hood is closed. After it fails to start and he gets out of the van, the hood is open.
It had been fairly early the previous day that the mercs had spread the gasoline inside the slaughterhouse, and so most of it would likely have evaporated by past noon on the next day; it would not likely have been still present on the floor in sufficient quantity to ignite with a dropped matchbook.