starter solenoid not working

[gmhardwick66]

I bought a procomp mini starter only to have it not work properly. alignment is perfect. when starting normally it just clicks, but not your typical starter solenoid click. very faint click. I metered ignition wire and have at least 12.5 volts when turning key. voltage does not drop even if keeping key turned as if starting for a while. battery is new. if I jump solenoid with screwdriver from battery lug to the small ignition wire lug...it works great. its as if the solenoid is not getting enough amperage through the ignition wire to the solenoid. I am going to swap the solenoid out with another one that I just removed from truck. so with that said the truck was running with the basic oem starter/solenoid. is this a wiring problem or just maybe a bad solenoid? I really want to use the mini starter.