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Think the shaft for the butterfly valve, which I think makes that entire assembly pretty useless. I think a welded disc in the middle of the H pipe on both sides would be way cleaner, the way @untamed did it. Because if you weld the valve shut, there is still going to be some leakage through the clearance between the valve and pipe, which I am pretty sure might cause some turbulence noise as each bank of the V8 fires. I do not know if you guys get what I mean.
Just to make sure, what @untamed did is something like this?
2019 Audi SQ5, 2011 Toyota Tacoma TRD 4wd, 2016 Ford Focus se Hatchback
That's what I thought. Although Untamedd had already removed his valve. I wanted it to look as stock as possible. I can see what looks like a weld on the picture but wanted to make sure that welding the shaft on the existing valve was what he did. Thanks.
Think the shaft for the butterfly valve, which I think makes that entire assembly pretty useless. I think a welded disc in the middle of the H pipe on both sides would be way cleaner, the way @untamed did it. Because if you weld the valve shut, there is still going to be some leakage through the clearance between the valve and pipe, which I am pretty sure might cause some turbulence noise as each bank of the V8 fires. I do not know if you guys get what I mean.
Just to make sure, what @untamed did is something like this?
Originally Posted by See63esS
That's what I thought. Although Untamedd had already removed his valve. I wanted it to look as stock as possible. I can see what looks like a weld on the picture but wanted to make sure that welding the shaft on the existing valve was what he did. Thanks.
yes mine does look like that picture. It was easy for me since I already had the valve taken out so could just insert the disc in the middle.
ps nothing wrong with trying to make it look as stock as possible but the dealer will look at the weld and say its not stock so thats something to keep in mind as well.
Just to chime in on this issue. I had this happen to me a couple of months ago. It sounded like a rattle snake on accelleration and decelleration. I took my car to the dealership because it's still in warranty. I was honest and told the mechanic that I removed the secondary cats and he was happy that i was honest. This saved him a lot of investigating, so he didn't say anything to my SA. A day later I picked up my car and the rattle was completely gone. My SA told me it was the butterfly flaps that they replaced.
My dealer was very good to me and they are going to replace exhaust flaps even though I have a modified H pipe etc.
This dealership has always treated me well so that is a bonus. Helps that I have bought 4 new AMGs in the last 5 years from them.
Interesting that this issue still is present in brand new cars, seems to be an area that they need to sort out from factory ASAP.
2019 Audi SQ5, 2011 Toyota Tacoma TRD 4wd, 2016 Ford Focus se Hatchback
Center section of my performance exhaust finally getting replaced by the dealer today. Special Thanks to Rhett McDonald for his information with the PTSS
The problem is weak tension in the on the three exhaust flaps L, R & Center. Request that your dealership open a PTSS Case with MBUSA Engineering and they'll get to the solution much faster - the tension needs to be increased on all three flaps. My car had 3 exhaust systems replacements and the rattling always came back - it took my dealer 8 weeks to identify the issues and 2 days to fix it once opening the PTSS case with Engineering.
Good luck!!
RM
Seconding this... but from Australia. This is a known issue and my c63s coupe with a 2019 build date still has this problem - even though the xentry appears to be from 2017. Took a couple hours at the dealership, apparently they tightened something up and greased my exhaust pipe (actually the valve actuator with a new special grease).
Seconding this... but from Australia. This is a known issue and my c63s coupe with a 2019 build date still has this problem - even though the xentry appears to be from 2017. Took a couple hours at the dealership, apparently they tightened something up and greased my exhaust pipe (actually the valve actuator with a new special grease).
Got the same issue here too. Noticeable if all windows and sunroof are open, COMFORT mode then I do a kickdown acceleration from 4th gear and exhaust button is pressed. It's like a metallic "kriiiiikikikikiiii" noise similar to marbles in a can or something (but it's not loud).
Are you in Sydney? Could you tell me which good dealer you went to?
Last edited by Jimmy_c63s; 12-26-2019 at 09:32 AM.
Got the same issue here too. Noticeable if all windows and sunroof are open, COMFORT mode then I do a kickdown acceleration from 4th gear and exhaust button is pressed. It's like a metallic "kriiiiikikikikiiii" noise similar to marbles in a can or something (but it's not loud).
Are you in Sydney? Could you tell me which good dealer you went to?
I'm in Adelaide - so can't help you there.
I'm pretty good at reproducing the sound now and this is how I did it:
1. Exhaust valve open. Window down.
2. Select gear where you can do a pull from 2000-3500 rpm safely and within speed limits.
3. Use about 30% throttle.
You can make the noise even more noticeable if you are driving next to a wall or brick fence (because it reflects the sound back). I requested a tech to ride along with me, made the sound happen and they agreed it was not something that should happen.
I'm asking my service guy now for the XENTRY Tips reference for the issue and will post it here once I get it.
I'm pretty good at reproducing the sound now and this is how I did it:
1. Exhaust valve open. Window down.
2. Select gear where you can do a pull from 2000-3500 rpm safely and within speed limits.
3. Use about 30% throttle.
You can make the noise even more noticeable if you are driving next to a wall or brick fence (because it reflects the sound back). I requested a tech to ride along with me, made the sound happen and they agreed it was not something that should happen.
I'm asking my service guy now for the XENTRY Tips reference for the issue and will post it here once I get it.
Looking forward to an update mate. Cheers.
If anyone else has any tips, experiences or ideas please update this thread. This is something that needs to be addressed and seeing as many of the 2016 cars are out of warranty now, I'm sure others would benefit
Last edited by Jimmy_c63s; 06-12-2021 at 03:32 PM.
Okay so here's an update, I've managed to make the rattle almost barely noticeable now.
Basically, went under the car and removed the exhaust flap actuator (motor) from the H-pipe and used White Lithium Grease spray and re-seated the spring. Worth a try before shelling out on a new exhaust.
It's pretty easy to access the H-pipe, I only jacked up one side of the car and used a a size 8mm socket (and spanner for the bolt at the top, closest to the heat shield).
The three bolts are a bit of a pain especially the bolt at the top. A spanner is best for the bolt at the top. Once that's taken off, you can remove the entire valve motor.
Side view of the "spring". Once you remove this motor, the H-pipe exhaust valve can be freely opened and closed with your finger. It's actually not very tight and moves very freely. By moving it with your finger, you can pretty much hear that rattle sound by moving the flapper on the H-pipe.
If you are looking for part numbers, the Exhaust Valve Motor for the C63S with AMG Performance Exhaust is A1909064500 and the plug is A0225452426.
Apply a very small amount of White Lithium Grease (about the size of a penny) where the spring is seated.
Also apply some around the actual exhaust flapper on the H-pipe where the spring of the motor sits. Make sure the spring is sitting nice and tight too.
Here is a view of the back of the exhaust flap motor
Refit the H-pipe valve
Doing this and making sure the 3 bolts that hold the actual exhaust flap motor to the H-pipe are nice and tight has made a massive difference. The rattle is no longer a "kriikriikrii" noise and more of a very low volume "crukcrukcruk" but barely there.
I would still prefer it to be completely gone so I will be waiting to hear if the dealer will honour the repair.
If anyone else has any tips, experiences or ideas please update this thread. This is something that needs to be addressed and seeing as many of the 2016 cars are out of warranty now, I'm sure others would benefit
plug in a valve simulator. Have the valve welded in close position. Problem solved.
plug in a valve simulator. Have the valve welded in close position. Problem solved.
Yep, exactly what i'll do if it plays up again.
I'm wondering if permanently closing the valve will cause any effects like loss of power? Would the car still be quiet in "quiet/comfort" mode?
Yep, exactly what i'll do if it plays up again.
I'm wondering if permanently closing the valve will cause any effects like loss of power? Would the car still be quiet in "quiet/comfort" mode?
theres no loss of power. comfort would still be quiet. valves in the mufflers not h pipe control the volume
Right!
So permanently closing it would produce a "deeper" sound in ALL modes even when cruising, huh? In quiet/comfort mode too?
its hard to explain it. i went through both permanently open and closed so in my head i know the differences if that makes sense lol. with it closed it acts more like stock but with it open it mellows down because the flap isnt closing so the car lost the raw aggressive sound that you get when you give it gas.
Okay so here's an update, I've managed to make the rattle almost barely noticeable now.
Basically, went under the car and removed the exhaust flap actuator (motor) from the H-pipe and used White Lithium Grease spray and re-seated the spring. Worth a try before shelling out on a new exhaust.
It's pretty easy to access the H-pipe, I only jacked up one side of the car and used a a size 8mm socket (and spanner for the bolt at the top, closest to the heat shield).
The three bolts are a bit of a pain especially the bolt at the top. A spanner is best for the bolt at the top. Once that's taken off, you can remove the entire valve motor.
Side view of the "spring". Once you remove this motor, the H-pipe exhaust valve can be freely opened and closed with your finger. It's actually not very tight and moves very freely. By moving it with your finger, you can pretty much hear that rattle sound by moving the flapper on the H-pipe.
If you are looking for part numbers, the Exhaust Valve Motor for the C63S with AMG Performance Exhaust is A1909064500 and the plug is A0225452426.
Apply a very small amount of White Lithium Grease (about the size of a penny) where the spring is seated.
Also apply some around the actual exhaust flapper on the H-pipe where the spring of the motor sits. Make sure the spring is sitting nice and tight too.
Here is a view of the back of the exhaust flap motor
Refit the H-pipe valve
Doing this and making sure the 3 bolts that hold the actual exhaust flap motor to the H-pipe are nice and tight has made a massive difference. The rattle is no longer a "kriikriikrii" noise and more of a very low volume "crukcrukcruk" but barely there.
I would still prefer it to be completely gone so I will be waiting to hear if the dealer will honour the repair.
If anyone else has any tips, experiences or ideas please update this thread. This is something that needs to be addressed and seeing as many of the 2016 cars are out of warranty now, I'm sure others would benefit
Thanks men.
I'm going to test this weekend.
Is valid for rear valves?
My rear valves sound like a old door open/close when I open/close the car or use the valve button.
One of the things you may be overlooking is by going 'straight pipe', each exhaust pipe will only hear the noise from only four cylinders per side at a time. The x- or h-pipes at least give you the sound of all eight cylinders from each exhaust pipe. Just sayin'....
My rear valves sound like a old door open/close when I open/close the car or use the valve button.
Thanks.
Yep, yours just need to be lubricated if they are squeaky. Use White Lithium Grease spray. It sprays out thick so don't use too much.
Take off the valve motor and inside the metal "funnel" section also apply some White Lithium Grease on the top of the actual exhaust flap spindle. You'll see this round spindle once you remove the black plastic exhaust flap motor assembly. That's what's causing the squeak in your back boxes (thanks to Alex for the pic).
Originally Posted by ///Bruce
One of the things you may be overlooking is by going 'straight pipe', each exhaust pipe will only hear the noise from only four cylinders per side at a time. The x- or h-pipes at least give you the sound of all eight cylinders from each exhaust pipe. Just sayin'....
10-20-2019, 01:02 AM
(actually the valve actuator with a new special grease).
