I was cleaning my throttle body today and noticed oil residue coming from the breather tube that runs from the valve cover to the intake (just before throttle body). I recently installed a new PCV valve, I also have a pre-existing engine knock noticeable on the highway under slight load, fairly loud knock under heavy acceleration which may or may not be related.

Any ideas? I'm not much of a mechanic, but I want to do as much as I can before I spend all my money at a shop.

BTW I have a 97 f150 4x4 w/ 4.6

 

Don't worry Ure self and I'm pretty sure its normal if its not a whole lot

 

The oil is usually from a bad PCV valve. Now that you have a new one in, take off the throttle body and clean it up good.

The knocking sounds like detonation. Try a higher grade gas and see if it stops. Then go from there.

 

check the PCV hoses & connections for seapage