newest forum but not 535i?
 

I have a question about the 08' 535 i's. There seems to be an exhaust cutout for one of the mufflers in the back. Is that really what it is and is it actuated by vacuum or electrically? I haven't found any info on the net about it yet. The exhaust is only flowing thru one side at idle and when revving up the engine, nothing from the cutout side at all. Just wondering about this since I want to change the muffler. TIA