How can you tell if a coil pack is bad on expedition
take a good look and do your research.
Here is a link that might help. http://easyautodiagnostics.com/ford_cop_ign/cop_ignition_ford_1.php
Mine (1998) has two (one left one right). Read the miss-fire code to determine left or right. Swap the coil packs and re-read the code. If miss- fire moves to other side, bad coil pack.
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