AMC didn't sell enough cars, to be able to say that their ignition module was problematic or not. Chrysler modules would fail, as does everything else on a vehicle, but only because Chrysler vehicles were capable of operating long enough, for components to wear out. I am of course excluding the vehicles, that left the factory with engine mount bolts missing, rod caps improperly torqued, ring gaps still aligned, transmission cooling line fittings not drilled all the way through, etc. (These are all from memory.) Sometimes, but not always, it would be caught in "Dealer Prep."
One thing they did, that I never understood, was about the middle of 1978, when they shortened the outboard end of the ignition rotor by about 1/16". Maybe the change had something to do with FCC regulations, or making the rotors cheaper. The guys in the Dodge dealer service bays were all suspicious of this change. A number of customer vehicles, with nothing else to explain a poor performance complaint, left the garage with an old style rotor installed.
Usually if the ignition module is bad, it is pretty easy to figure out. Everything else is working, but there is no spark. If this vehicle kept coming back for the same complaint, the mechanics failed to diagnose the real cause, choosing instead to throw parts at it. The guys at the Dodge dealer got pretty good at diagnosis, again because Chrysler sold enough vehicles for them to get the practice they needed.
Earle
maintenance so