Has anyone ever experienced a weird whistling/squealing noise from driver side muffler bank 2. Looking to figure out what that noise is so I can resolve the issue. Thanks

06 flying spur

 

Hello Makaveliism,

When does this sound happen...at Idle, gradual acceleration , hard acceleration or? This information may help in determining what is going on. In conjunction hopefully the sound isn't a "hooting" like noise.

 

Sound happens at idle.

 

Okay that helps. Can you isolate where on the bank 2 exhaust that the "whistle" disseminates from?

 

At the rear muffler. I'm thinking it's the valve on the muffler.

 

Agreed...that's where I was going. The flap may be slightly unseated. Check the valve after startup up if it actuates

 

i have a situation that after starting car in the morning the muffler is very noisy and is squeling too. after 30sec i hear sound of a flap or smth, and it is getting quiet.

always thought it is normal when you start cold car after longer stop.

should i take a look smth?

 

Yes there are (2) muffler diverter flaps one on each side/bank which can be seen inside the rear mufflers with a flashlight. Start the car and quickly with a flashlight check the operation of each flap on both mufflers. The flaps are controlled electronically by solenoids (2) that use vacume to actuate the (2) flaps.

 

will do, thanks @1eapplebaum - what operation is correct, what is wrong? what is expected behaviour?

 

The flaps start in full pass-through of the muffler as in "sport mode" as per transmission shift option. Then they close the click we hear allowing a muffled exhaust note. The whistle I suspect is one of the flaps isn't fully seated and thus the whistle.

 

Issue resolved. It was the vale in the muffler on the driverside. I pulled the vacuum lines going to the mufflers and capped them, noise has been gone completely for 48hrs. Valves stay open the whole time now.

 

no other way to fix this and make operational without noise?

btw - bruceR said it opens fully on "s", so in all other conditions the flaps are fully closed or they are modulating openess depending on what? can you explain the mechanism and its role for the car?

 

I'm pretty sure I could have cleaned the valve with carb cleaner or something or just spray it with the same stuff the hellcat guys have been using with their noisey active exhaust. I just don't like the idea of spraying stuff that gets as hot as a muffler does. Bentley isn't loud at all with the valves open so it doesn't bother me. Unlike my granturismo which is pretty loud with valves open the whole time.

 

so others spray the break cleaner or other kind of chemicals?

there is nothing to disassemble?

 

here is what others do.