Exhaust rattle with EVM Module on decel
Thread Starter
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2019 AMG GTC Solar Beam Yellow
Exhaust rattle with EVM Module on decel
Has anyone had this issue? I installed the EVM Module and when I decel at any speed, I get a God awful metallic tin can rattling sound ONLY when I have the valves set to the 100% open position.
When I change to the factory position, it stops. I assume it's the butterfly valves but I thought this device actually prevented the issue?
Car is a 2019 GTC w/ removed secondary cats. Appreciate any insight.
When I change to the factory position, it stops. I assume it's the butterfly valves but I thought this device actually prevented the issue?
Car is a 2019 GTC w/ removed secondary cats. Appreciate any insight.
Member
Joined: May 2022
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GTR
My AMG GTR with catless downpipes has the EVM with no issues, but my BS has had the rattle in the exhaust since new, even when it was stock!
,,,, its a crappy design and getting a new exhaust does not guarantee it does not happen again!
,,,, its a crappy design and getting a new exhaust does not guarantee it does not happen again!
Member
Joined: May 2022
Posts: 154
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GTR
You can try replacing the actuators, but if that does not work, it would need a new exhaust, which on the BS is $10K!
... or you can straight pipe
... or you can cut it open and try to fix it yourself, but welding / cutting would be required.
... or you can straight pipe
... or you can cut it open and try to fix it yourself, but welding / cutting would be required.
Member
Joined: Sep 2017
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From: Chicagoland
Schwinn
Had the same happen to me, pulled the exhaust out was able to find a flap actuator and replaced it but it had the same noise. Took it to dealer and they said i was internal in the muffler system. Which I thought was BS, you know how they like to replace everything.
Car was on MB Extended Warranty which didnt cover the Muffler assembly, but after some persuasion ($) they got it covered. Removed the EVM and installed DPs and never missed the EVM module.
The noise it made was awful, hated driving the car.
Good luck with it. It was either a new muffler or aftermarket. You cant leave the flaps open manually as I found out that will cause a CEL and limp mode. That is because every time you start the car the ECM tests the resistance in the actuators and the resistance. That is what i was told when I asked here.
I would of been perfectly fine with opening them and not having a quiet mode.
Car was on MB Extended Warranty which didnt cover the Muffler assembly, but after some persuasion ($) they got it covered. Removed the EVM and installed DPs and never missed the EVM module.
The noise it made was awful, hated driving the car.
Good luck with it. It was either a new muffler or aftermarket. You cant leave the flaps open manually as I found out that will cause a CEL and limp mode. That is because every time you start the car the ECM tests the resistance in the actuators and the resistance. That is what i was told when I asked here.
I would of been perfectly fine with opening them and not having a quiet mode.
Thread Starter
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Joined: May 2023
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2019 AMG GTC Solar Beam Yellow
Well this is wonderful. Car literally has like 2100 miles on it. What's weird is it doesn't do it when the EVM is set to factory settings (Button #2). At least not yet, I guess. Probably coming. It sounds awful. Like I'm dragging something metal behind me.
I'm surprised nobody has found a fuse that you can pull to leave them open all the time. I know that the Vettes (If I'm remembering right) and F-types for sure had a fuse that would disable the flaps.
I would do dp's in a heartbeat but don't want to have to tune out the cel. Blah...guess we'll be pulling the exhaust and seeing what we can find.
Appreciate all the comments and insight!
I'm surprised nobody has found a fuse that you can pull to leave them open all the time. I know that the Vettes (If I'm remembering right) and F-types for sure had a fuse that would disable the flaps.
I would do dp's in a heartbeat but don't want to have to tune out the cel. Blah...guess we'll be pulling the exhaust and seeing what we can find.
Appreciate all the comments and insight!
Thread Starter
Senior Member
Joined: May 2023
Posts: 312
Likes: 146
2019 AMG GTC Solar Beam Yellow
Had the same happen to me, pulled the exhaust out was able to find a flap actuator and replaced it but it had the same noise. Took it to dealer and they said i was internal in the muffler system. Which I thought was BS, you know how they like to replace everything.
Car was on MB Extended Warranty which didnt cover the Muffler assembly, but after some persuasion ($) they got it covered. Removed the EVM and installed DPs and never missed the EVM module.
The noise it made was awful, hated driving the car.
Good luck with it. It was either a new muffler or aftermarket. You cant leave the flaps open manually as I found out that will cause a CEL and limp mode. That is because every time you start the car the ECM tests the resistance in the actuators and the resistance. That is what i was told when I asked here.
I would of been perfectly fine with opening them and not having a quiet mode.
Car was on MB Extended Warranty which didnt cover the Muffler assembly, but after some persuasion ($) they got it covered. Removed the EVM and installed DPs and never missed the EVM module.
The noise it made was awful, hated driving the car.
Good luck with it. It was either a new muffler or aftermarket. You cant leave the flaps open manually as I found out that will cause a CEL and limp mode. That is because every time you start the car the ECM tests the resistance in the actuators and the resistance. That is what i was told when I asked here.
I would of been perfectly fine with opening them and not having a quiet mode.
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Member
Joined: Sep 2017
Posts: 220
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From: Chicagoland
Schwinn
Yes that I exactly what it does, but the ECM can still test them for resistance from closed to open.
If you just open the mechanical part in the muffler and let’s say weld it open and leave the actuator unplugged it won’t work as it will throw a code. I even asked if I left the actuator plugged in and not assemble to the muffler part and was told it checks the resistance and if it doesn’t sense any which in the case of not being on the actual flap it wouldn it will still throw a code.
My problem is that it wasn’t a actuator problem but the internal part of the flap inside the motor.
I blamed myself for awlays opening the flaps before starting the engine. I don’t know if that did it or not.
If you just open the mechanical part in the muffler and let’s say weld it open and leave the actuator unplugged it won’t work as it will throw a code. I even asked if I left the actuator plugged in and not assemble to the muffler part and was told it checks the resistance and if it doesn’t sense any which in the case of not being on the actual flap it wouldn it will still throw a code.
My problem is that it wasn’t a actuator problem but the internal part of the flap inside the motor.
I blamed myself for awlays opening the flaps before starting the engine. I don’t know if that did it or not.
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Super Member
Joined: Jul 2014
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.
Very frustrating.
There are methods offered by owner of Eurocharged in Minnesota that repair the rather poorly outsourced design of the OEM valve with a better design - plz search my previous posts.
This method is rather involved.
Also, there are several who can source the necessary emulators/resistors to trick ECU into thinking they are working properly, while your valves are fixed open - search Facebook Group: AMG GT Owners
Best of luck
There are methods offered by owner of Eurocharged in Minnesota that repair the rather poorly outsourced design of the OEM valve with a better design - plz search my previous posts.
This method is rather involved.
Also, there are several who can source the necessary emulators/resistors to trick ECU into thinking they are working properly, while your valves are fixed open - search Facebook Group: AMG GT Owners
Best of luck
Thread Starter
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2019 AMG GTC Solar Beam Yellow
Thanks again everyone! I really appreciate all of your knowledge.
Because I only get the sound with the flaps 100% open and on decel, we may have a plan of attack. So if it works, I'll update the thread.
Because I only get the sound with the flaps 100% open and on decel, we may have a plan of attack. So if it works, I'll update the thread.
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2019 AMG GT R
was it really the ASR/Renntech EVM causing the noise? I also just got an ASR module but if theres even a slight chance that it will cause the valves to rattle then id rather just pass on it.
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2019 AMG GTC Solar Beam Yellow
reviving this thread to ask if you were able to figure out what the root cause was?
was it really the ASR/Renntech EVM causing the noise? I also just got an ASR module but if theres even a slight chance that it will cause the valves to rattle then id rather just pass on it.
was it really the ASR/Renntech EVM causing the noise? I also just got an ASR module but if theres even a slight chance that it will cause the valves to rattle then id rather just pass on it.
I actually ended up wiring the spring so it stayed open but I think the issue is with the baffles. I just plan to get a different exhaust down the road.
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2019 AMG GT R
Nope...I still get the metallic rattle sound on decal after nearly 2 years. Hasn't gotten worse and I basically ignore it. I honestly don't know what the connection is with the EVM and the rattle. The exhaust valve failure is very common.
I actually ended up wiring the spring so it stayed open but I think the issue is with the baffles. I just plan to get a different exhaust down the road.
I actually ended up wiring the spring so it stayed open but I think the issue is with the baffles. I just plan to get a different exhaust down the road.
ps if the valves ever go bad, check out the replacement valves that asr has; better build quality than oem.
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2019 AMG GTC Solar Beam Yellow
Out of curiosity, do you have the CETE module or asr/renntech one? Ive read a few posts now from ppl using CETE complaining about rattling under braking my so i wonder if its something wrong with CETE or its just a coincidence.
ps if the valves ever go bad, check out the replacement valves that asr has; better build quality than oem.
ps if the valves ever go bad, check out the replacement valves that asr has; better build quality than oem.
