MJP_43

This is my first AMG so I'm not familiar with how the cars's driving style is set up.

My question is "Why does the transmission stay in gear after a brisk acceleration?"

You hit the gas from a stand-still and the car takes off, nice, but when you let off the trans stays in gear, like it was in manual mode but without the little numbers on either side to show that it's in manual. This happens in every mode, even REDUCED. Not a good thing if you're in SLIPPERY Mode where I'd think you should be in the highest gear possible and lowest torque map.

I asked the dealer tech expert and he said something like, "...well the car thinks you're going to stay in it and holds the gears." This make little sense to me, maybe the someone on this site or from Großaspach can explain why the trans is set up this way.

Here are a few customer "product improvement" suggestions (if anyone from AMG is listening):
How about a customer set-up option when we pick up the car to set the variables for all the drive modes? For instance;
1) I'd like the car to start in the last mode I selected.
2) I'd like the exhaust flaps to be open in SPORT mode.
3) SAIL mode should work in COMFORT mode
4) I'd like to control the aforementioned transmission shift behavior.

I know some of this probably has a "liability" component but if you buy an AMG you'd like it drive your way.

superswiss

The tech expert is essentially correct. The transmission can't read your mind. It only has your inputs to go on, so if you are gunning it, it assumes you wanna drive in a sporty manner and if you let off, it assumes you are slowing down for a corner and therefore holds the gear. This is desired behavior in a transmission that's setup for sporty driving. If you let off during brisk driving the transmission shouldn't upshift, so that it stays in the right gear to accelerate again. The transmission and chassis algorithms adapt to your current driving style. The mode you are choosing sort of sets a base line and influences the algorithms, but your driving style causes the algorithms to adapt and deliver the expected response. You can always override the transmission with the shift paddles.

As for your "product improvement" suggestions, some of that would be nice, but the reason for why things are the way they are has mostly to do with regulations. For example the EPA and the equivalent agencies in other countries require that a car starts in the mode that its fuel economy was certified in. The 2019s, at least the C63/S have a so called emotion start. You hold one of the shift paddles while starting the car. That triggers a cold start with the exhaust valves open. Not sure if the C43 has it, though.

jonathan358

Just override it with the paddles. It stays at a lower gear for a couple seconds after kickdown because it thinks you are/will be driving hard. You should be glad this happens, imagine overtaking a car and suddenly it upshifts and you lose all your torque. Next thing you know you are in involved in a head-on collision.

I agree with your first and second suggestions. My default drive mode, once warmed up, is Sport and I'd like more noise. Going to purchase the ASR module to make that happen.

I would hate my engine disengaging in Comfort though. If I wanted to save gas, I would be in Eco Mode...

MJP_43

Thanks for the rely. Makes sense but my issue is with the "assume" part. We all know what that implies.

So as far as transmission learning goes, I get it. But my feeling is that this performance shifting behavior should be limited to Sport and Sport+ modes. Driving algorithms in Comfort or Slippery modes should be more conservative, if I need to hold a gear I can use the paddles. Now I have to "opt out" of the algorithm driven shift mode, I'd rather "opt in". I like to control how things work on the car, not vice versa. To quote Konrad Gunther, "I need no assistance to drive!" [FYI, he's the German guy in the Infinity commercials from last summer]

Another issue I have is that this "sporty driving setup" is going to get me into trouble by encouraging a littler too much speed. I'll figure it out eventually.

I also understand the EPA driven stuff. The C43 starts and idles at a high rpm, 1200-1500 or so for a bit, sounds a little F1-like which is cool. My CLA did the same thing, and with the Sport Exhaust was pretty snotty at start-up. The reason given was that this would heat the catalyst up faster to start working to reduce emissions earlier. The exhaust flaps seem to be closed at start-up but the other engine parameters are probably max'd out for a short time for the same reason..

superswiss

I guess to some extent it's preference. I'm not familiar with the C43 at all and I haven't taken delivery of my C63S yet, but I'm familiar with the high performance versions of BMW and Audi. My current daily is a 2013 Audi RS5. While these cars have a Comfort mode, they are still tuned in a sporty manner. They are docile if you drive them docile, but if you give it the beans, regardless of the mode, they will happily comply and wake up. Audi takes the kind of approach you are describing with their S models. They are rather complacent in the normal modes and it's infuriating a lot of owners. I personally don't wanna have to change drive modes first before I get the desired response when stomping it. I specifically like that these cars do respond properly even if I'm currently bumbling around in Comfort mode. Often the moments where I need all the go it has come up unannounced, so I don't wanna have to fiddle with the drive mode first. Some of the main complaints that you can read on Audi forums with the S4/5 is that owners get caught in somewhat iffy situations, because the car's response is lethargic unless it's in full attack mode.

jonathan358

Agreed, this is a big problem with Audi's although some like OP may want that response.

On an unrelated note, I wish you can pull and hold the paddle ONCE to change gears and set it back to automatic. As of now, you have to change gears and then hold upshift to set it back meaning you have to change gears twice...
A lot of times I drive in Sport but still want to stay in high gear for fuel efficiency. If my foot is a bit heavy, the default gear will be 8 but I want to switch to 9 which requires two paddle pulls...

superswiss

You can just pull the paddle once and shift to 9 and then just let it be. It will revert to D automatically after a few seconds.

MJP_43

Just to be clear I'm not complaining about the C43 transmission, I just want to understand how and why it works the way it does. Having said that, if I could control the behavior I'd modify it for the less aggressive driving modes.

As far as Audi goes I have no direct experience, but I can't imagine that they don't have a "button" under the accelerator pedal to downshift to the lowest possible gear, or just hold the left paddle to downshift.

It's really just a personal preference that I think we'd all like to control.

This also has to do with the driving scenario. If I need to merge onto the highway or just haul ***, it's just 2 clicks of the drive mode to go from Comfort to Sport+. I'm a button pusher so I like controlling things this way. 2019 C63's and 2020 C43's have the optional "Drive Unit" control on the steering wheel like the race cars.

superswiss

Yes, Audi's do have the kick down switch and on more recent models you can hold the downshift paddle to downshift to the lowest possible gear. That's not really what I'm talking about. It's more the in between and the quick hunting for the highest gear. You basically have to push it all the way though to get a response, which is not necessarily desired.

Yes, the new AMG Drive Unit is awesome and I'm looking forward to it in my C63S. I particularly like that you can push the drive mode knob to activate Individual mode, so this does make it quick and easy to engage one's preferred settings for say sporty driving.

MarcusDubya77

Shoot, my only gripe is the location on the toggle for the modes. Wish it was on the steering wheel, but that would present its own problems. There are definitely reasons that it defaults to comfort mode. I would assume a lot has to do with why any of them start up in comfort mode. They, MB, figure that the average buyer for these cars will be in comfort mode a majority of the time. It is a lot easier (and economic) for the driver to have to manually change it thanit start up in prescribed settings. Just my 2 cents.

Malar

Facelift sails in Comfort, since there's no ECO Mode.
Its perfect because why wouldnt you want that? It won't Sail if it sees you need the Engine Brake, for example if you have a car slowing down in front of you.

if you don't like how the Transmission behaves you should've done a longer Testdrive with the Car.
Don't know what you guys do with your Dealers, but i got a Facelift C43 for 14 Days to have the Chance to fully Check every Scenario.
Wouldnt buy a Car without that chance.

sieglo

Facelift only sails in individual.

Malar

Then you should contact your Dealer to get your Car fixed Sieglo.
Since my Facelift sails in Individual, Slippery, Comfort, Sport and even in Sport+.

Cosworth2000

The 7G+ and the Newer 9G+ is programmed to stay longer in the gear if you put the gas fast. Example, when you pull off at the lights faster than normal by pressing smoothly. This is normal in every sporty transmission setup and hence you are given the manual mode to control the transmission to your own liking. The only time a transmission will when to downshift on demand is when you hit the brakes.

Hope that helps,

sieglo

You're incorrect. Sailing only works in Individual mode in 2019. From the manual:

"Glide mode is activated if the following conditions are met:

• The ECO start/stop function is activated.
• Drive program [I*] is selected with the drive setting "Moderate" or "Reduced".
• The speed is within a suitable range.
• The road's course is suitable, e.g. no steep uphill or downhill inclines or tight bends.
• you are no longer depressing the accelerator or brake pedal.

Glide mode is deactivated again if one of the conditions is no longer met. When Active Distance Assist DISTRONIC is active, glide mode is not available."

My 2019 only sails in Individual mode -- the expected behavior.

Malar

So now i have to tell my Car that its doing it wrong :-/
Poor C43 is probably confused and think he's a Diesel! Sailing in every Mode, every day i drive the Car to work.
But the Internet-Guy told me i'm wrong, so i guess i have to return the Car to Factory because the Display is faulty, showing it Sailing all the time!

(Btw, to make you even more confused, my Car sails even if i'm pressing the Brake as long as theres no other Car in front of me ;-) )

Malar

My faulty Car, probably there was an Awolnation Album playing in the Factory, because it SAILS

superswiss

This is not something I really care much about, but I just wanted to say there might be a misunderstanding here. In the pics you are showing, your car isn't sailing (gliding). You are just off throttle and the fuel is cut off. Every car today cuts off the fuel when letting off the throttle. When the car is gliding, the display shows a symbol that looks like a sailboat. I believe the current drive mode C,S,S+ at the bottom right changes to the sailboat looking symbol. Or maybe it's displayed somewhere else in the digital dash. In addition the transmission disengages from the engine, so the rpm go down to idle. In the first picture for example, your car is definitely not gliding given the rpm, neither is it gliding in the other pictures as the rpm is above idle rpm in all your pics. Anyway, the other thing you have to be aware of is that each country is different. Looks like you are in Switzerland, whereas other who commented here are in the USA. Different regulations in each country affect features like this, but that seems like a moot point as in none of these instances your car appears to be sailing.



EDIT: Also wanted to add that the supposed fuel savings in glide mode are questionable at best. As I said above, every modern engine with fuel injection completely cuts of the fuel supply during deceleration when the foot is completely off the throttle and the engine is literally burning zero fuel. The wheels via the transmission is what keeps the engine turning at that point. The problem is you have engine braking in this situation, so the car slows down and you have to get back on the throttle to maintain speed. So the idea behind glide mode is to remove engine braking and let the car roll along under its own momentum and lose very little speed. The only speed loss comes from the rolling and wind resistance, but no longer will the engine slow down the car. Problem is while in glide mode, the engine has to burn fuel in order to keep turning. So in order to really save fuel the car has to roll far enough under its own momentum to make up for the idle fuel the engine is burning. It's been the long standing understanding that coasting in neutral, which is what glide mode really is, doesn't save any fuel, and in the USA coasting in neutral is actually technically illegal.

Malar

You're Quoting the Manual for the old, non-Facelift C43. There's also written that you have to be in the Eco-Mode, which the Facelift doesnt even have.
There is no Multifunction Display in the Facelift since you have the digital Display. There's also no boat appearing, but the fuel usage goes to "charge" instead of staying at the value it shows when you're let off the throttle and the engine is breaking.
As shown above from my Pictures i sailed already KILOMETERS down a Mountain without having to engage the Engine once.

See below another Pic of an C200 that has an Eco-Mode and currently Sails = Same "charge" display.

superswiss

@Malar No, I quoted the MY19 owner's manual. I'm afraid, but you don't understand the glide mode and what the cars are doing in those pictures. What you are seeing is recuperation by increasing the alternator voltage and give the battery an extra charge. Nothing to do with glide mode. In glide mode, there's no recuperation, because the transmission is decoupled from the engine.

Malar

There is NO Boat symbol in the Digital Display, are you able to somehow comprehend that?
I'll stop writing here now since i don't discuss a matter thats clear. You know that the Manual wasn't updated for the Facelift?
I'm sure i rode down 8km of Mountain Road without stepping on the Gas once without Sailing

Bye