My 2017 SVR during cold start is loud but about 15 seconds it cuts out as if I turn the switch of Dynamic mode, which I don't. When I do drive away it can get very loud if I push it and cracks and pops like the best of them. I had a 2018 R that was about the same in crackles and pops but during cold start it kept loud and did not quiet down as my 2017 SVR is doing. Vacuum line issues or is this how it is? Just weird. Not sure if anyone has pic on what and where the vacuum lines are located as I would like to search them out. Thanks in advance.

 

Mine is loud at start and then quiets down, unless I put it in dynamic mode.

 

Your SVR is doing exactly what is is supposed to. In fact your ex- 2018 is the faulty one

 

I beg to disagree, my MY18 stays noisy until the engine has warmed up sufficiently to drop the revs to idle. I can preempt the drop by selecting D, but left to itself it's quite happy to shout for several minutes.

 

haven’t you just agreed with me ??
his 18 wouldn’t drop down at anytime

 

But you said his 2018 was faulty, which it isn't.

 

With my 2015 R, the valves are open when you start up (since there is no vacuum) but quiets down in about 5 seconds once the valves close. That's what I consider normal. RPM's is different than valve functionality...don't confuse the two.

 

Is it supposed to quiet down after 10 seconds or so even when I keep it in dynamic mode and when the revs are still higher than typical idle as it warms up? When I click dynamic on and off at this stage no difference. But Dynamic does make a difference when I am driving, and I get the louder crackles and pops as well. Just surprised it quiets down so much during cold start.

 

If I don’t hit the button, it’ll quiet down as it will be set to normal mode. If I engage the button, then it will remain loud. Again this is on my 2015 so other years may work differently

 

Possibly post a video? The timing is key here. How long after quieting down does it remain in the high RPM before the RPM settles?

Another quick test could be to pull the fuse for the valves to see if it makes any impact on your cold starts.

 

Late to the party. My 2017 SVR does the same (I think!). Loud when I start it and remains loud until revs drop which takes a bit longer on a cold engine. If I pop it in reverse to back out of the driveway it quiets down

So if I'm out early I start it with garage door closed and pop it straight into reverse. Then give the door time to open (important step!!)

 

I will have to pay close attention next time, but I think my 2017 V6 S also goes quiet when the RPM's come down after cold start, even in dynamic mode. But when driving, it's loud in dynamic mode.

 

Rob I know exactly what you’re talking about. I had a 2017 SVR and this is working as normal. What’s happening is the valve is simply returning to the half closed position (despite being in Dynamic and exhaust open). The solution you’re looking for is simple: pull Fuse 15. I did this halfway into my ownership. This will force the valve to be fully open all the time and result in the entire cold start sequence to be loud. I have a video on my IG @amg.svr showing the full loud cold start. Let me know if you have questions I’m happy to help

 

Thanks XEC. I did exactly that and pulled fuse 15 and presto it did not quiet down. Very cool and worked like a charm.

 

This is the normal (and intended)/pattern and my 2015 operates in exactly this way.

 

I have noticed that the valves open at a much lower RPM on the SVR than they did on the R.

 

This is what my 19' does unless I put it right into Dynamic.

If fuse 15 is pulled, then the valves remain open no matter what?

 

yes. i removed the fuse temporarily but didn’t like it as i lost the ability to quiet down the car if coming home late so not to wake up the kids. Fuse went back in and I just pull the switch at start up…easy.

 

My 2016 V6S does the same thing.