Problem starting my car (electrical problem)

I have a 95 AWD Eclipse (manual trans). I am having problems starting the car. When I switch it on and start it, it seems that it's not sending enough electricity (volts) to the starter solenoid. I checked the starter and battery and they are in perfect condition. Also checked wires from battery and starter and they are good. The problem seems to be in the starter switch which lies in the back of where you put in the key. It's a plastic type switch that has a male plug and inside it has two copper discs that have a special kind of electrolyte (green) grease. I opened this switch a few times and cleaned it a little bit. I used some sanding paper on the two copper discs. What I did helped for a few days, but the starting problem keeps coming back. I haven't replaced this switch yet. I am trying to look where the fault is, but the only thing I think of is that switch is worn out or maybe there's a problem with the wires going from the switch to the starter solenoid. I'm a planning to install a remote start switch, which I don't know will help. NEED HELP!!

could have been from the slide hammer damage...