What kind of pot is it?
Some of the ones I've gotten, esp surplus have been pretty nasty so mem's idea of cleaning it is good.
Electrical contact cleaner from an auto store will work and I think it is cheaper than ratshack and probably closer.
Plus you get a LOT more of it.
Something you can do right now is to check for a bad connection. If you soldered wires to the pot then check the solder work.
If you used stranded wire in a proto board get rid of it and use the proper size solid wire until it's time to make it a permanent device then use stranded wire or of if it's PC mount solder the pot to the board.
If you have one jammed in a breadboard consider soldering the proper gage solid wire to it and trying that.
I've had one of the small disk ones crack when I bent the leads to insert it in a board but there was nothing that looked wrong. Only wiggling it and using a meter found it.