The Positive Crankcase Ventilation valve on the 2004 Ford Taurus sends partially burned gases from the crankcase to the combustion chamber. Locating the PCV valve on the Taurus is merely one of its challenges. The valve should be replaced per recommended maintenance schedule servicing for the Taurus. Once it stops rattling, it allows oil to bypass the valve and quickly clog up the air filter and air intake system.
Open the hood to the 2004 Ford Taurus and follow the air intake system where it meets the valve cover. The PCV valve is located on the backside of the engine.
Follow the air intake tube below the intake manifold. If the Taurus uses a heated PCV valve, disconnect the wire harness first.
Use the ring-tipped needle-nose pliers to turn the PCV valve counterclockwise and unseat it. Twist it while pulling upward to release it from its seated position.
Inspect the intake hose to ensure it's not dry rotted or cracked where the PCV valve plugs into it.
Insert the new PCV valve into the port and twist clockwise to secure it.
Replace the intake hose to the inlet of the PCV valve.
Connect the wire harness--if applicable--to the heated PCV valve.
