Did you notice any smoke from the exhaust while driving? Hoses split, clamps come loose, so those would be the first things to check. There might be oil in the intake piping, but is it pooling or just a mist? Misting is normal, pooling is not. The PCV system is known to have shortcomings. So much so that Ford released a redesigned valve cover to help combat the problem! Valve cover gasket problems in the area of cylinder #3 (driverside along the firewall) are also well-known, can cause power loss and misfires.
And yeah, any idea on codes set in the PCM/computer?