hi,the pollen filter on my xsara 14i h/b is near the floor on the passenger side.remove the cardboard type panel under the glovebox,you should feel a plastic square.at the bottom of this plastic,you should be able to either remove a couple of screws or slide a part of the plastic box to the right.and the panel should then be seen.remember to put the filter back the right way.
Bernie rubble
May 2008