Exhaust Rattle
#1
Exhaust Rattle
Out of nowhere a rattle started from my exhaust today. Its only audible when giving throttle. Butterfly valve failure? The car is tuned and has the secondary resonators cut out - should i have them welded back in (something i wanted to do anyways) and re-flash factory before taking it in?
Last edited by Zeker; 04-26-2019 at 05:17 AM.
#4
To follow up here. Cats went back in and im not happy about it - preferred them out. The good news is the repair is being covered by MB under warranty (so good thing i put them back).
Exhaust had something rattling inside of it so there is a new system on order from germany. Should have it back in a few days
Exhaust had something rattling inside of it so there is a new system on order from germany. Should have it back in a few days
#5
Member
Mine seems to have the tiniest of rattles that I only notice when. Off the gas and slowing down almost like a tiny pebble got into the exhaust. It’s not noticeable to most people but for the **** type like me.
Anyone else sense that. Slowing down no throttle.
It’s not the normal decelerate noise.
Anyone else sense that. Slowing down no throttle.
It’s not the normal decelerate noise.
The following users liked this post:
doctorG (07-29-2019)
#6
Member
Mine seems to have the tiniest of rattles that I only notice when. Off the gas and slowing down almost like a tiny pebble got into the exhaust. It’s not noticeable to most people but for the **** type like me.
Anyone else sense that. Slowing down no throttle.
It’s not the normal decelerate noise.
Anyone else sense that. Slowing down no throttle.
It’s not the normal decelerate noise.
Going to take it in soon to see what dealer thinks.
Anyone else have any thoughts?? Thanks!
#9
Member
#10
https://mbworld.org/forums/coupe-roa...ml#post8252812
#11
Member
If someone identifies something that I can clearly go to the dealer with I’d appreciate it. Thanks!
#12
Member
Had the exhaust rattle - very annoying and apparently its the butterfly exhaust valve when in open position
Naturally you hear it at lower speeds when the car is in S / S+ / race mode
Problem fixed by my AMG specialised tech who applied a specific grease that is ordered in.
No rattle now but will likely need to be greased again in a couple of years.
C63S definitely has a similar rattle according to him
Naturally you hear it at lower speeds when the car is in S / S+ / race mode
Problem fixed by my AMG specialised tech who applied a specific grease that is ordered in.
No rattle now but will likely need to be greased again in a couple of years.
C63S definitely has a similar rattle according to him
#13
Had the exhaust rattle - very annoying and apparently its the butterfly exhaust valve when in open position
Naturally you hear it at lower speeds when the car is in S / S+ / race mode
Problem fixed by my AMG specialised tech who applied a specific grease that is ordered in.
No rattle now but will likely need to be greased again in a couple of years.
C63S definitely has a similar rattle according to him
Naturally you hear it at lower speeds when the car is in S / S+ / race mode
Problem fixed by my AMG specialised tech who applied a specific grease that is ordered in.
No rattle now but will likely need to be greased again in a couple of years.
C63S definitely has a similar rattle according to him
#14
From what I can tell, loosely; Stock GTR - Comfort mode= closed OR Sport/Sport+/Race= ~75% open to 100% open depending on mode and throttle... My assumption is the new mapping will eliminate that 75%-100% and make it fully open. If you get the Renntech EVM, it will give you the 0% or 100% unless you turn off the EVM and just let it do stock noise. Eliminating that in-between area puts less wear on the butterfly flap allowing it to keep the sound consistent and superb. Otherwise you risk flutter and/or sticking which can and has impacted turbo boost.
I am no expert, just a new owner troubleshooting via the internet and my tech.
#15
Newbie
My tech told me that there is a one page guidance on the rattle (GTR) and that it is "normal" for a supercar. He followed that with an if they wrote a document that length as a bulletin then they are getting a lot of complaints about it.... I was told that they narrowed it to a mapping issue which should be released in a few months. Other members have been given that same guidance, but over a year ago and still have no resolution. It was recommended to me to get the EVM from Renntech, but I have not had anyone verify that fixes the issue if the exhaust is already rattling.
From what I can tell, loosely; Stock GTR - Comfort mode= closed OR Sport/Sport+/Race= ~75% open to 100% open depending on mode and throttle... My assumption is the new mapping will eliminate that 75%-100% and make it fully open. If you get the Renntech EVM, it will give you the 0% or 100% unless you turn off the EVM and just let it do stock noise. Eliminating that in-between area puts less wear on the butterfly flap allowing it to keep the sound consistent and superb. Otherwise you risk flutter and/or sticking which can and has impacted turbo boost.
I am no expert, just a new owner troubleshooting via the internet and my tech.
From what I can tell, loosely; Stock GTR - Comfort mode= closed OR Sport/Sport+/Race= ~75% open to 100% open depending on mode and throttle... My assumption is the new mapping will eliminate that 75%-100% and make it fully open. If you get the Renntech EVM, it will give you the 0% or 100% unless you turn off the EVM and just let it do stock noise. Eliminating that in-between area puts less wear on the butterfly flap allowing it to keep the sound consistent and superb. Otherwise you risk flutter and/or sticking which can and has impacted turbo boost.
I am no expert, just a new owner troubleshooting via the internet and my tech.
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Beeast (01-22-2021)