My 95 Z28 has a bad miss, last time it done this a changed the opti spark and it was good to go. So this time i bought a cap and rotor from orielly auto. Replace and still has the same miss. Not for sure what its called but the part that screws to the center with two screws, is it possible for it to be causing this?thats the only part of the opti that wasnt replaced. I did a search on here but didnt have much luck..and I have checked all my plug wires and changed coil.

 

So it seems the rotor wasnt in the kit i ordered. Is this part that normally goes out on the opti spark?

 

Rotors have been known to come loose, and some to actually fall off. A bad rotor can cause the symptoms you have.

Usually it's the optical part that ends the life of the opti. You need a new rotor, or try to clean up the one you have.