stillcap2

Hi all - I received my C43 coupe a few weeks ago, and generally it has been a pleasure to drive. I am, however, having one issue that seems to come up in S+. Sometimes when I am accelerating from a stop (even at normal/soft accelerations), the car starts rocking/jerking back and forth about 2-6 times like it is stuck and unable to switch gear. It also actually won't go forward more than a few feet when this is happening, even though my foot is on the accelerator. I take my foot off the accelerator and, once the rocking has stopped, reapply and it goes forward fine.

Similarly, when coming to a stop in S+, the car will jerk back and forth very noticeably/uncomfortably. It seems to be more than just a regular downshift. This happens when I slowly come to a stop over a longer distance. Can't remember if it happens when I come to an abrupt stop.

I'm not sure if this is normal, something I am doing wrong, or an issue with my car. This is my first sports car, so I haven't run into anything like this before. Would appreciate if anyone has any suggestions/advice. Thanks in advance!

Bueller178

Sounds like you need to visit your dealer.

auditoamg

Uh... Totally agree.
Before this gets worse and unsafe.

5ilver-5urfer

This happens after the car has 100% fully stopped and you are about to accelerate again? People experience this in a manual if speed and RPM's get too low while in a high gear...but not from a complete stop.

inhartwetrust

I have something similar where the car (from a dead stop) gets "stuck" in first gear and very abruptly revs up and down, rocking the car, while it begins to progress forward. It mostly happens when I've applied medium pressure to the pedal...not enough ease for a slow smooth take off, and not enough punching it to register that I'm looking to redline it from the start. I describe this very much as the timing of the gear shifting being stuck and it just revs up and down in gear 1, without shifting up to 2, or running 1 up to redline.

Similarly, as I come to a stop, I also experience the jerks...this comes as it downshifts gear by gear and achieves higher RPM this time. This doesn't make for a smooth stop, but being in S+ and it trying to maintain high RPM in each gear, it makes sense.

All of the above happens only in S+ for me and I assume it is because it is trying to maintain high RPM per the programming.

Cocheche

I experienced something like that at the beginning in Sport+ as well. After some tries, I've reached to the conclussion that I was stepping too hard on the pedal. In that mode (Sport+), I recommend to be as gentle as you can with the pedal, and you'll get the reaction that you're looking for.

rwg1919

Mine has done this also... mainly in sport+, but once in sport. Happened a couple times early on, and not since. I manually shifted up when it happened last...

tmoneyC450amg

This is bad...MB needs to step it up with their trannies...the 450 experiences instances of dead pedal during times of quick re-acceleration after deceleration. Only way for me to cure it is to drive in M mode

stillcap2

Thanks for all the replies. Your experiences sound right in line with my own. Is the answer then simply that we need to very gently accelerate from a dead stop until we are in higher gear? Or should this not be happening at all and so we should take it to the dealer?

Tej7

I would call your dealer and see if some sort of software update can be done. I wonder if resetting the tranny would do anything. This has also happened to me the very first day, only in sports+. The car bounced back and forth in 1st gear. I'll try to reproduce it if I can, and take it to the dealer to show them.

Lionel_Hutz

Yikes. Surprising to see so many people immediately respond that they're having similar issues. Sounds like a major problem.

5ilver-5urfer

It seems like most people that experienced this only had it happen a handful of times when driving the car fairly new. I would suggest anyone that experiences this consistently actually reach out to their dealer and have the honor the warranty!

Tej7

I wouldn't jump to conclusions just yet. This isn't a major problem either, more of an annoyance. Whether or not it is a real issue and if it'll lead to future problems is yet to be seen.

inhartwetrust

Correct, in my case. I don't recall experiencing this after the first few days.

The slight jerks as high RPMs are achieved on downshift while braking is consistent, but I believe that to be by design and I don't find it to be annoying.

stillcap2

Did a bit more testing last night. It appears that this also happens when I am accelerating after a rolling stop at a stop sign, where I get down to about 5-10 MPH, then accelerate again. I'm trying to accelerate smoothly, but this still happens. I think that I may still be in a higher gear when I accelerate after the rolling stop, which causes my car to stutter and rock back and forth.

I guess I'll try to get the issue resolved with the dealer.

Tej7

Go into the AMG menu on the instrument cluster and try to keep track of which gear you are in when this occurs.

arnold0523

umm, im having this issue today. 4 days after delivery. hope it gets better after break in. please update us if you hear any updates from your dealer, thanks

tivoboy

so, this "issue" has been around for some time on C450 with the tranny 7g. I think it's more about something else, than the tranny though. Obviously tranny and engine sw.

I used to find it, and still do sometimes when I've been accelerating, and de-celerate, coming to a stop or a slow down, CA stop is the worst and then try and get back on the throttle more than just gently / casually, and boom the car sputters and lurches and does this on/off lurching. It really quite annoying and I haven't found anything that can correct it. I've tried resetting the tranny now that the car is broken in and that didn't cure it.

PeterUbers

wow wow

this is the typical experience of the mct, cannot believe the new 7g tronic does this!!

JK123

Hi All

replying from Australia.

For what it's worth, I had the exact same experience while test driving the c43 coupe with the sales agent next to me. It happened about halfway through a 45 min test drive on pulling away from the kerb. In sports (or +) mode. I wasn't flooring the accelerator - just a gentle speed increase at which point the shuddering/rocking occurred. The agent couldn't explain it and it never happened again. I got the feeling something was awry with the transmission hunting through the gears somehow. Hopefully it resolves with use - don't some of these newer car transmissions "learn" your preferences over time?! Either that or a software update. Nevertheless the drive was so impressive that I have placed one on order!

avilajf03

This happens to me too! Not very often but occasionally on sports +. I'm going to try and shift up manually next time it happens to see if it helps. Keep us posted if things change for you guys.

Tej7

I personally have not experienced it again since the first day. Shifting up manually or changing modes completely does indeed cause the lurching to cease.

vintage59

I am seriously thinking of ordering a C43, however, coming from Japanese brands, I get concerned when I hear such transmission issues with brand new cars. I have driven the C450 and really loved it and the C43 is at least as good from what I hear. I was hoping the C43 9speed transmission would not have some of the problems that C450 owners have experienced.
I am patiently waiting and monitoring the threads. My 16 year old Type Still goinf strong but would love to get a C43.....

FastE

Everyone needs to realize the gear ratios are very tight on the C43 - much tighter than the C63. Driving in Sport+ gracefully isn't easy but it definitely occurs after a major slow down and then punching it too fast. Your own foot rocking at this moment simply exacerbates the problem. I only just got mine - but noticed this on the demo and found myself adapting already. I don't think it is a problem - it is like popping the clutch too fast on a standard. I will check back on this forum after a few more days - trying to take it easy on the new car...

5ilver-5urfer

From what i can gather, it seems to pop up when in Sport+ when you're sending some major power to the engine and then suddenly hit the brakes hard, and hit the gas hard again. I've experienced it too. Would it have played in to my purchase decision if I experienced it prior to purchase - nope. It's a car - every car has its quirks. The options are probably a software patch soon to prevent this, or they leave it as is for a few years and then tackle it down the road.

It's an interesting time for engines and their respective trannys....the N55 being replaced by a B58 that hasn't quite proven itself yet...and now this.