To be certain, you should:
* Consult your owner's manual: This is the best source for the exact location for your specific vehicle.
* Look at a diagram: Search online for "2003 Ford Crown Victoria ignition coil location diagram". Several diagrams should pop up showing the engine bay layout.
* Use a repair manual: A Haynes or Chilton repair manual for your car will have detailed diagrams and instructions.
Be cautious when working near the engine; allow it to cool completely before attempting any inspection or repair.