I never had one fail. I've had electronic ignition control units poop the bed, plenty of ballast resistors, etc.
I do recall having to replace one 02 sensor on an '85, and one air charge temp sensor.on an '89. But timing and choke adjustments were the two biggest offenders. That and/or vacuum leaks, bad secondary wires/plugs, low voltage issues, carb (usually float), fuel system (weak fuel pump or vapor-lock).
Sometime around '86 or '87, Chrysler had a fleet service bulletin floating around that indicated 95% of the problems attributed to Lean Burn were all of these other problems, and most of those false reports came from dealership mechanics. The line techs just didn't want to deal with the level of diagnosis required to properly fix those cars. I recall my local dealer in the 80s had a SCC analyzer just gathering dust in the corner of the shop. Today, that analyzer has become the OBD scan tool.