Understanding the appropriate procedure and diagnosis codes for a particular study question is an important part of analyzing Medicare data. These codes are very specific and can change from year to year as new codes are added and others are discontinued.
There is no wear-out factor in the coil itself other than thermal cycling and the damage it may cause. Boots and wires do age, resulting in reduced insulation value over time. The key to correct ignition system diagnosis is to understand the details of how the system you are working on really functions. PAGE:
Ignition Coils - Waste Spark Style. Then there is the waste spark ignition system. Auto manufacturers got clever at some point and realized that they could halve the number of parts in the ignition system (compared to the typical coil on plug system), if they fired two spark plugs from one ignition coil.