I see trucks hauling away loads of crushed vehicles every day, it’s not usually the engine that fails.
They were probably junked due to either automatic transmission failure, electrical problems or body rust.
A micro ceramic-Wankel might make a good small-engine power unit however, like a natural gas generator for your home, that runs 24/7.
Add that to a this kid with the "Graphene" ultra-capacitor breakthrough, and you have a potential co-gen unit w/ storage and then if some low-cost solar comes along we are in game changer mode for sure...