Originally Posted by deanthecrabman
Some residue is normal from the PCV. If you aren't using oil, you are probably jumping the gun. I've got an 01 with 105k miles, and I haven't lost a drop of oil, yet I see a little residue in mine. My mileage is about the same as yours. There is a diagnostic.
I agree. When the plenum is leaking there will be large amounts of wet oil puddling in the plenum. You should also experience pinging and use a small amount of oil.
If it looks like a dry brown residue, that would be normal.
Finally, if you're still not sure, run the diagnostic.