Wish you had listed the year, make, model of car and the engine in it! Oil could be leaking down through the valve cover seals around the spark plugs or you may have worn valve guides.

I know that the valve seats are bad, I am just trying to find out if that emery cloth may have worn the contact points. Seeming how I never had a problem cleaning them until I started using it

sounds like those plugs have been cleaned too many times ! if oil is getting on the plug,s firing tip then you have bad valve seals ! if the oil is just on the plug,s threads then the valve pan gasket is leaking !

You would be better fixing the problem that is causing the plug fouling.

My engine leaks oil into the cylinders quite on a regular basis. I have to pull my plugs and clean them off every once in a while and it runs great afterwards. Usually I will use a wire brush, a pick, and some brake or carb cleaner and it works great. But I tried using some emery cloth and it worked a whole lot better. I just did it again recently and it worked great once again, but I seen to have noticed that after a couple a days it started running like it is misfiring. Could the emery cloth have worn down the spark plugs? Distributor cap and rotor, wires, and plugs have all been replaced within the past few months