View Single Post
      12-21-2012, 04:37 AM   #4
FormerRotor's Avatar
Drives: 2011 335d, M-Sport
Join Date: Jan 2012
Location: MD

Posts: 1,436
iTrader: (4)

I believe that this acts as acoustic dampening, but it may also have something to do with the spring-loaded secondary air assembly in the box. Yes, the filter is installed with it on (it's glued on).

My Picture Threads (Oldest to Newest): 1 2 3
Join BMW CCA! (Use my link and I get credit )
FormerRotor is offline  
Reply With Quote