The olfactory bulb, or the nerves that detect scent molecules, are closely tied in with the brain's amygdala (which processes emotional response) and hippocampus (which handles memory formation). Put simply, scents make us react on an emotional level. That's likely why gasoline triggers a pleasant response.
some people do some people don't it's just desire the people who are classified as petrol sniffers gasoline contains benzene which has the nice fragrance.
