Sorry, I know this thread is about a week old but Im not sure what you mean by oil on the filter? I know some filters require oil to be sprayed on after a cleaning to help prevent dust particles from flowing through to the engine, such as my SRI intake filter. What I would do is go buy an intake cleaning kit, clean it down real well and re-oil it and if needed buy some sort of barrier to seperate the filter from the engine bay (I know it has a name but I cant think of it). Essentially its a partial box that attaches to the intake tube and blocks heat and debris from hitting the filter.

Mine is a K&N and it needs oiling....

one of my friends said to get a dry filter which required no oiling

i hate to discard my K&N, spent nearly 130 dollers for the whole set up :-(

Also forgot to tell you i did a realy smart box for the filter with heat sealing foil. works well and looks good too...

How do you know it works well? Can you see intake temperatures on a gauge or something?