The DPFE for the 5.0L/302ci Explorer is between the firewall & intake manifold, at the top of the intake manifold. If you follow one of the tubes from the EGR Vaccum Solenoid, it will lead you directly to the DPFE.
If you've changed the PCV valve before, it's just above where the PCV is located. The DPFE is almost flat and in a rectangular shape on the top back of the Intake Manifold. It is a little tricky to get to, but nothing to difficult.
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