Hi....
Is this a Zetec engine? It is the most absolute engineering mess I have ever seen. They place a tork screw under the thermostat housing that one must remove to get the steel tube back enough to get the PCV valve out...You end having to dismantle far too much just to remove a simple PCV valve.
Another thing to check is the rubber tube in the back which connects to intake manifold area. I found my newly bought 98 Merc's being sucked flat and wasn't working hardly at all. PCV filter in air filter box must be clean in order to pass air to valve cover then through oil seprator to PCV valve and through steel pipe, rubber tube to intake....Could have been made so simple, but Ford did not care to do.....Even the rubber tube is special in the back with a sharp 90 degree bend and a $17 price tag, when you can find one at the dealer....?????????
Duane Koss / Blue Springs, MO