While Ian and Barley Lightfoot are on their quest for the Phoenix Gem, Barley claims his van, Guinevere, gets an "empty stomach" despite the gas gauge stating it's full, but Barley states it "doesn't work that way". The gas can he has in the back of his van only has a few drops left in it, so he hops onto his van to search for a nearby gas station, until Ian asks if there was a magical way to get gas. Then he tries using the Growth Spell, but due to Barley constantly interrupting him, Ian ends up shrinking him.
While small, Barley locates a gas station, so the trio walks over there, but upon getting there they meet the Pixie Dusters, who comes wheeling through with their large motorcycles. After scaring a gas station worker away, the team stacks up to each other to get inside. Inside the building, the dozens of Pixie Dusters are messing around with the snack bags and the drink machines. Ian ends up interfering with one when headless Wilden Lightfoot steps on one by accident.
Ian and his father fill up the gas can, when Ian hears Barley arguing with a Duster. He quickly grabs Barley and hurries to leave, but ends up whipping Wilden around and knocking over the gang's motorcycles. They get furious and start to chase the boys on the highway, with Ian driving Guinevere due to Barley's shortness. Eventually they lose them after they crash into a line of traffic cones.
A couple of Pixie Dusters appear at the end of the film, in remodeled Manticore's Tavern with mugs and playing darts.