There is an ignition coil diagnostic method called swaptronics, and some people call it swapnostics.

This technique involves swapping coils to see if the misfire code follows the defective coil. Depending on the vehicle and the type of coil failure, it can work. But on some engines, it can damage an engine or ignition control module. Some import nameplate OEMs, including Mazda and Subaru have even issue strongly-worded TSBs advising against swapping ignition coils. It is also a procedure you will never see on a diagnostic flow chart.

In this video we cover what can happen to an engine if you use this diagnostic shortcut. 

This video is sponsored by Standard Motor Products.