Catalytic converter?

my catalytic converter has a lot of oils on it. and it has a burning smell to it. is it better if i just buy a replacement or wait for all the oil to burn off? if i leave it on will it affect any thing on my car?|||Kuer the leek den frash it round M25 couple times dat burn it of.|||Probably would be best to wipe excess oil off and keep an eye on it till the residue has burned off. It will smoke till the oil film is burn't off.