I second Dan here, Juan!
My opinion here--Re-route the PCV valve to the breather hose/tube, or to the air inlet duct, or leave it alone. DO NOT just cap off the PCV valve and think that it's OK.
PCV= Positive Crankcase Ventilation valve, if ya didnt know that. As Juan likely discovered here, cap off the PCV valve, and you have decreased the crankcase's ability to ventilate, that can lead to pressurization in the crankcase. Forcing oil out thru seals/gaskets. Blowby gasses get past the rings and the resulting pressure will find the path of least resistance.
Remember we call it "PCV Re-routing" NOT "PCV Valve Sealing" or "Crankcase Sealing"!!
Folks, if you have a question about what you are doing, ask it here! Think about what you are doing and what the effects of your actions can be.
So Juan, did you notice any correlation between when ya capped that pcv off and when your Taurus started leakin' oil? I'd either do a proper re-route or just hook that PCV back up stock, but un-cap it! Oil pressure senders usually have their own seal or gasket, or are just a self-sealing pipe thread where they screw in. You could put a bit of Teflon tape on the threads, but I've found it usually isn't necessary.
Again- the object of PCV re-routing is to cap or otherwiase seal off the manifold vacuum source the pcv is routed to. Then just re-route the pcv hose/pipe to either the breather hose/tube//pipe or connect in to the main air inlet duct. We are eliminating a major vacuum leak, but ALSO giving the pcv valve (and therefore the Crankcase) a way to breathe, and therefore preventing crankcase pressurization.
Lastly--again my opinion-- go ahead and play w/ your own vehicle--but know what you are doing before you apply the pcv re-route to someone else's car. Ask if you are unsure. Do not just seal off both ends of a PCV valve system!
Tracy G