I have a 94 with a 460 that has had 4 distributors and two pick-up coils fail. It runs great for a few minutes or as long as three weeks but eventually goes ou. i can put the original distributor in and it runs now but very poor (the reason I put the first distributor in).

I'm lost on this one. Any help is appreciated.

 

Very common if you are using rebuilt distributors.
You need to put a in a NEW distributor or replace the Stator (PIP) in your old distributor with a NEW one.

 

The last two were new distributors. We also replaced the PIP in the factory distributor it ran fine yesterday and would not start today. Is there a resistor or something I need to check that is letting to much voltage through to it?

 

Are you checking for spark when this happens?
Does the fuel pumps run all the time when it does not start?
If no spark & running fuel pumps then this sounds more like a bad computer than a PIP sensor to me.

If no spark try probing the top wire of the ICM with a test light. If you get spark each time the test light makes contact then the PIP sensor and the ICM are good.
If this works try removing the SPOUT shorting bar or unplug the PCM Computer and see if you have spark them.