Where is the ignition coil on a 2004 5.4 Ford Expedition?

On a 2004 Ford Expedition with the 5.4L Triton engine, the ignition coils are located on top of the spark plugs. They're not a single unit, but rather individual coils, one for each cylinder, directly mounted to the spark plug tubes in the valve covers. You'll need to remove the plastic engine covers to see them clearly.