Hi all,found out the problem with my wife's S80 t6 is....MAF Sensor,but,there is still a big hole on the bottom of the air filter box,is it suppose to be this way? Someone please help me...thanks
Mark

 

My 2000 had a plastic pipe about 1" in diameter with a rubber cover sealing it.

My 2001 has the same plastic pipe but does not have a cover because there is no hole through the pipe into the air box. If you have a pipe like this and there is no hole, you do not need to seal it off. If you have a hole, seal it off.

If the hole is a rectangular hole on the lower housing, it could be because your cold air duct is missing. Should not cause any major issue if it is missing unless you want maximum horse power from engine in warm weather. Mine was a PIA to put back on so I left it off.

If you think you have a problem with the MAF sensor, you may want to buy MAF sensor cleaner and use an air gun to clean it.