IIRC the foam insert was there to further quiet the air intake. It serves no real purpose and I ditched mine years ago. It is a good idea to clean out the bottom of the airbox every once in awhile.

Finally rolled my 98 S70 T5m out of the garage and into it's parking space for the winter! Lots of interior cosmetic work (door cards, headliner,etc), brakes, steering rack, front suspension, engine tuneups and some goodies, painted all horizontal surfaces myself (have a few touchups left). Full tin...