Hi all, my first post after much lurking so please forgive me if I'm in the wrong section.

I bought a 2023 E53W4 AMG with performance exhaust about a month ago. Since driving home from the dealership, I was very clearly able to hear the exhaust crackle and pop around 3500-4500 RPM when downshifting/lifting off gas pedal in sport+. I have about 1500 miles on the car now, but I'd say at around 1200 miles, after refilling the gas with 93 octane I never hear those crackles anymore. I think I can still hear some aggressive pops while upshifting in sport+, but never those satisfying crackles and pops that made me fall in love with the car anymore. I don't drive it in sport+ unless I'm pulling hard on the highway so the ECU/TCU shouldn't have learned a calm driving behavior for sport+, but even still I tried a TCU reset multiple times last night and unless I did it wrong there was absolutely no difference. Even getting up to 6-7k RPM on downshifts I still don't hear any crackles at all with valves open. The instructions I was able to find were quite old/outdated so if anyone could shed some light on how to do a TCU reset on a '23 Mercedes I'd happily give that a try too. It's not in my head either - I recorded several videos driving when I first got the car and you can very clearly hear those beautiful pops, but now it's pindrop quiet when lifting off the gas pedal compared to back then. I've also refilled the tank several times since then at different gas stations so it can't be a bad batch of gas either. The exhaust sounds seem to have disappeared out of nowhere.

I have a service visit scheduled in a few days for this but I'm not sure how much they'll be able do to help. Has anyone else with a new Mercedes with performance exhaust experienced this? What else can I try to fix it on my own? I thought maybe the valves were not opening correctly but at idle I can still hear the exhaust get a little louder when I press the performance exhaust button.

Any suggestions/help are much appreciated.

 

Maybe the exhaust flap cover is not opening (like in the comfort mode)

 

If you can’t figure it out get a valvetronic exhaust and leave it open.

 

So I just got back from the dealer and they said nothing is wrong with the car, the valve actuator is opening as intended - just that learning the driving style and end of break in period could've stopped the burbles... Makes sense as I'm mostly just driving around town in comfort and only throw it in sport+ on the highway for a bit. Really disappointing though. Might do an ecu burble tune/downpipes but I'll have to ask my service advisor about warranty issues.
Thanks for the advice though!

 

Aloha…know this is an older post but right around the same time I had a check engine light come on and the. It did go off.

What I noticed immediately was my snap crackle and pops are gone. I need to find the paper work but they changed a few parts under the hood.

If you are in Sport + and no snap crackle and pops there is something wrong.

My advice if you have not gotten this fixed already, is have them run full diagnostic and mention the check engine light came on.

Car is another animal with Sport+ and Snap crackle and pops….

 

Thanks for the insight, honestly I think I figured out the issue - The snap/crackle goes away if you leave it parked outside in cold weather for too long, on my car at least that's what I observed.
I had been parking this car for months in sub freezing temperatures, and the pops went away. But when spring rolled around they came back randomly one day. This year when it got cold, the pops disappeared again. About a month ago I moved to a building with underground parking and after I consistently parked indoors for ~2 weeks now the pops are back, in the middle of winter.
I'm a little confused on this since just recently I parked it for one night outdoors in cold weather, and the pops went away the next day.. But they came back after a fresh tank of gas that same day.
Just boggles my mind that whether this car will snap crackle pop seems to depend on the temperature where you park your car overnight. But for anyone having this problem, just park somewhere warmer for a while. Or just tune the thing

 

and... I thought the winter and summer blend affected it.