Ok, here is what I know about the CPS. Having just replaced mine and correcting problem, I ordered a new Bosch CPS to have on hand. I kept the old one, so I decided to check it out. As I suspected, there are no moving parts, it developes a pulse by detecting rotating cogs on the crank. I checked the circuit with an Ohmeter and got the same readings with the old and new CPS. This isn't proof positive that the old one is OK, there could be a break in the circuit that only manifests itself when the engine is warm but it could also be a matter of cleaning the contacts and replacing it back in. I will do a little more research this winter.

 

Yes, I have long suspected that CPS failures are more about the contacts than the magnet coil.

 

This has been raised before and you are in a position to save people $$$ so go for it.

Possibly some dielectric grease on the terminals at assembly would be the answer?

If there is no movement then the wires inside should not break, although the stuff the wire is coated with could breakdown with heat, but if it breaks down why would it be OK at times?
Maybe this part needs an air duct or air deflector to cool it.

CPS evaluation from Benzworld.