Wow some people should not be under the hood of a car.
- A distributor is a piece of metal with a gear attached to the end of it that spins off of the camshaft xxx
-Note that a rotor, and a distributor cap are not a distributor but rather parts that are attached to the distributor xxx.
- As far as your question about losing power, the year make, model, engine size, whether its fuel injected, a TBI unit, or carburated is needed to make an educated guess at your problem.
-Yes distributors do wear out, the shaft in the housing will wear out one day, but would take many many years to do this.

-All of the parts on a distributor are replaceable unless the housing or the shaft are bent/ tweaked etc xxx.
- C,mon wake up. Hope this help