... maybe this is another episode of my being overly paranoid about my car's health: when I filled up today at BP station, the last drips of diesel out of the nozzle were a little bit "frothy," and the surface of the diesel in the tank had a slight foam on the surface. It settled and disappeared and seems to be fine now. Is there anything abnormal about this? Is it just from air in the fuel pump? I asked the station attendent, and he looked as though I'd just asked him to perform quantum physics. Is the froth anything to worry about?