I believe those BMW models like the 6-er has the same. My 335's left exhaust has a vacuum hose and flap on the left(viewed from rear of car) that is suppose to be closed but will open as you gas the car above 3000rpm or so. This I understand is to prevent droning/rattling at low rpms especially when driven in D mode. Thats also why the 2 rear mufflers are connected. This feature is suppose to so called add some back pressure when you launch the car.
At check done at BVO yesterday suggest that the flap is loose. Bernard could use his hand to 'shake' it. This lose portion has been giving some rattling noise when I push start the car esp going upslope....a bit irritating. So what shoudl I do?
1. Replace the whole exhaust>>buy from someone else.
2. Claim warranty>>from PML and should be a headache!
3. Saw off the exhaust and get rid of teh vacuum thing altogether and replace with a straight through pipe.
4. Do nothing and suffer silently everyday, ie Garm Gio !
At check done at BVO yesterday suggest that the flap is loose. Bernard could use his hand to 'shake' it. This lose portion has been giving some rattling noise when I push start the car esp going upslope....a bit irritating. So what shoudl I do?
1. Replace the whole exhaust>>buy from someone else.
2. Claim warranty>>from PML and should be a headache!
3. Saw off the exhaust and get rid of teh vacuum thing altogether and replace with a straight through pipe.
4. Do nothing and suffer silently everyday, ie Garm Gio !
