P0304 Mazda -repeated failure

Question

engine overhauled by Miata dealer. New camshaft, one rod, one piston. P0304
back to dealer-no problem detected.
P0304
back to dealer-npd
I replaced camshaft position sensor P0304
I replaced spark plugs, cylinder four coil and associated plug wire P0304
back to dealer-replaced camshaft position sensor. motor ran w/o issue for 1000 miles. then P0304
Initially, the issue was a simple miss, then normal operation. Now, always leads to total shutdown. After a rest on the side of the road it will start and run properly, for a while.
It doesn't seem the Mazda dealership is capable of diagnosing the problem. Help me. Please.

Answer 1

The Miata is equipt with a ignition mobilizer, for the anti theft, you may just have to completely remove the system , there is also a possibility its the ignition switch system