I purchased a salvage GT with screws in the vacuum lines that feed the muffler flaps - droned and too loud for me any time I was accelerating even a little or driving uphill. This didn't sound like a Bentley, but then again I wanted a Bentley and not a teenage car.... Of course, everything opens and sounds great when you really need the acceleration - sounds like a Ferrari then - even when stock - great engineering!!! Now that you know my preferences, and with respect to those that want the extra noise I am including pictures. Access is easiest as previously stated - only 11 nuts and bolts hold on the under panel (10 on mine as one tab was already broken).

Flaps can be moved by hand and the 1st pic shows the vacuum line going to the flap actuator - these are at the very back of the muffler. When you pull the actuator in, this pivots the flap and you can move it by hand and hear the metal flap move in the metal muffler.


The 2nd picture is that of the solenoid that actuates the flap (black electrical item with the hose and wire and white letters at left of the photo), although I agree this is probably similar to what the sport mode already likely does for you. If you really want teenage sound, perhaps you want to straight pipe the mufflers, but that is not for me! For those not so mechanically inclined, the solinoid and the actuator are connected by the vacuum line that you have been talking about taking off the actuator and plugging with screws, as mine was.

 

I just picked up a 2006 Continental GT today with 27k miles. It is in great condition but has a number of small issues I hope to address. One of them is a sporadic metallic rattle at the drivers tailpipe when the car is idling. It goes away when I rev the engine. I did push lightly on the damper with a screwdriver at the rattle went away. It seems the baffle might be loose when the car is at idle. Any ideas?

This forum is great. I have been learning a lot as I was looking for the car. Any ideas would be appreciated.

 

Hello ​​​​​​@Bigdog63 ,
It would seem that your baffle shaft is worn or failing, I have two stock rear mufflers available, or you could just cut them off and stright pipe the rear.

I have the AWE Supersports exhaust system on my 05 GT with the 2011 Supersports engine transmission package installed in my Gt rebuild.



Johnny

 

Thanks Johnny.

Any idea what provides the tension to hold the baffle closed? Does the vacuum caused by revving the engine pull the baffle open? Could it be a vacuum hose leak in the line to the part that drives the baffle. I don’t see any springs in your photos.

I will get a video tomorrow and post.

 

Well I was able to spend some time today under the Bentley. I did notice a few things. The actuator that moves the flaps was a little different than the ones in the other pictures. They had a black bottom not white. After investigating a little it appeared that the actuator was not pulling hard enough on the flapper to close it all the way and hold it closed. I was able to push on the flapper with a screwdriver and the rattling stopped. My thoughts are that there is not enough vacuum to hold the flapper shut tightly. It could be that there is a leak in the tubing before the actuator or the diaphram in the flapper actuator is getting weak and can't pull the flapper hard enough. It looks like the flapper actuator is part of the muffler as it was welded on. I decided to try plugging the vacuum line that feeds both mufflers and it worked like a charm. No more rattling and the sound is not that much louder. The check engine light did not come on.

I did notice a few things. All of the connections on the vacuum lines had flexible rubber lines connected to the part or tee the the smaller diameter hard plastic lines were inserted into the rubber lines. The date markings on the tubes were all from 2006 so I think they are original. I wonder if this was the fix Bentley came up with for the small hard vacuum hoses cracking at the barbs.




Actuator (black bottom) with my finger on the flapper shaft

Rubber line from the actuator to the small vacuum line.

Tee from main vacuum line to the muffler flappers. This is where I plugged the line.

Golf Tee in rubber hose and stainless cap screw in smaller vac line going to flappers

I clamped the golf tee in place with a worm clamp and wrapped it in electrical tape so it does not cause any issues. I also put the lines back in the holders so if I decide to revisit the issue later it will be easy to reverse what I did today.

Thanks again everybody for the advise on this forum. My next project is checking all the drain hoses.