True fuel is discussed in this episode, first with the 1980 phenomenon ""gasohol"" and with real gasoline at a motorcycle race. The gasohol segment takes Lisa to a rural factory where corn kernels, with enzymes and yeast, are fermented into alcohol to be mixed with gas. Lisa and the farmer then use it to drive a tractor. The Bloodhound Gang is confronted with ""The Case of the Dead Man's Pigeon.""
