Please, I need some feedback from anyone who has has similar experience or knowledge of how these transmissions are supposed to work in a C43.

The problem was that the transmission was sharply upshifting from 4th to 5th when coasting, which was unexpected. It's been doing this for a long time and it really started to concern me. It felt like the trans was on the way out.

I brought the car in for Service B and told the advisor about my concern with the trans. They ended up replacing the valve body (under warrantee) because the transmission finally tripped a code.

But the problem is unresolved; the trans still upshifts when coasting just more "softly". And now, ALL shifts are not as crisp as they were when the car was new. Frankly, it shifts like crap.

But, before I make this an issue with the dealership I'd like to know if this behavior will be somehow considered to be within "Normal Parameters" by MB.

The Invoice says that the valve body is for a 725.0 / 725.1 trans. I don't know if this is significant.

My sense is that the unexpected upshifting is a quirk of the trans that has been masked by softening all of the shifts. Not the problem I wanted fixed.

 

Take it back in and let them know about the issue.......... Obviously, you can argue that the old valvebody had better shifts.

 

Check the part number and see if it is a reman, it might be a bad reman. If not, also make sure they check the fluid, they might have used not enough fluid or used the wrong fluid, get them to scan for codes if there are new codes popping up. Finally, get them to reset transmission adaptation and if that doesn't work get them to manually adapt the transmission.

 

UPDATE:

Brought the car in for service today - takes more advance scheduling to get a loaner these days - and they're opening a "Case". That means there will be a lot more mechanics checking things...to me it means "New Transmission". I'll let you know.

But the real news is that I got to test drive a brand new 2023 C43. These are my take-aways:
1) Performance is awesome, no turbo-lag - as expected with the electric turbo - go fast now! Nicely responsive even in "Comfort" mode.

2) Suspension supposedly stiffens with speed but I didn't have enough time at the wheel to evaluate this. So, no Comfort, Sport, Sport+ modes. But the AMG hydraulic suspension is smoother, more compliant in regular driving. So the problem of a stiff ride in every mode due to conventional sport springs seems to have been solved. Comfort really means comfort. I'd prefer more control of the suspension and trans shifts for that matter. I don't like all of the aspects of a "Smart/learing" car. What am I, an idiot? I know what I want to do, unfortunately some people don't and MB is catering to them. FYI, the car fan continues to run after the car his turned off. Circulating coolant and oil to preserve the turbo I'm guessing. But some people will complain; "My car is still running after I turn it off."

3) The DCT shifts nicely but not as sharp as I expected. The shifts were a little, I don't know how to describe it, "hesitant/softened"? It's a very subjective assessment on my part and again, not a lot of seat time. But not the "SHIFT NOW" I'm complaining about that my car stopped doing, the way it originally shifted is not there; 1st Bang, 2nd Bang , 3rd Bang ... (Scared me the first time I heard this, sounded like a gunshot! Oooh, aaah, me likey now. Puts rice burners with fart pipes on notice!)

4) The exhaust note was "nice" but not the same as my V6, but there are pops and crackles. The unaware wouldn't guess that this was a 4-cylinder though.

5) Ahh, the 4-wheel steering, I had one opportunity to put it to the test on an off-ramp. I had the front tires squealing, just a bit, and felt in complete control. NICE!

6) I HATE THE "B" PILLAR. It compromises left visibility and, oddly, the mirrors don't go as far out as would have liked. I leaned left and could still see the left quarter. I have my car set further. It seems that there is still a blind spot somewhere out there.

7) New MBUX is "dodgy". With no center controller it's either steering wheel buttons or touch screen and the steering wheel controller is not straight up-down, left right. Up-down is set up on a diagonal, strokes need to be about 20-30 degrees up-outboard(left)/down-inboard(right). And even the Touch screen takes some getting used to, again one drive for 10 minutes. With more time I'm sure it can be dialed-in. But you have to adjust the seat so that you can reach it comfortably. Kinda defeats the point of reducing driver distraction.

8) Heads up display needs to be in RACE-Mode to provide Speed, RPM and Gear.

Overall there are improvements in drivability with no loss of power due to the 4-cyclinder. I'm trying to find out how much boost AMG is pushing. I'm guessing something north of 20psi. MB is going to sell a lot of these!

I'm holding out for the new CLE 53(?) which should be quite similar to the new C43, but with only 2 doors.

 

Thanks for sharing your impressions on the W206 C 43, either way hope you get your car fixed soon.

 

After a spirited drive, the fan also runs after shutting off in a W205 nothing different really but it is less often on the W205.

 

The suspension of the pre-facelift is worse than your facelift W205 2019, that is one of the greatest compliant on the pre-facelift W205, so it felt like a dream driving the facelift, would probably blow us pre-facelift owner away if the suspension improved even more so than the W205 facelift on the W206..,thanks for your review.

 

Final UPDATE:

Picked up the 43 on Friday after almost 3 weeks in the shop. Took 2 communications to Stuttgart to review the case and 2 trans "resets" to arrive at the conclusion that the trans performance is within specs.

I'm not unhappy but it still wants to upshift while coasting, just not as hard a shift as before. The trans is a little dysfunctional; it wants to shift when it wants to, and Not shift when it doesn't. Easy work-around using the paddles.

I'm thinking that there's something going on with the trans adaptive "learning". I probably drove it harder when the car was new because it was awesome, and that's what the trans "learned". After the new valve body I was easier on it and that's what it learned and consequently shifted softer. Now I'm driving more aggressively and more often in S+ mode. That aught to teach the trans GOOD shifting!

1st, BANG 2nd, BANG 3rd.... Bye for now.

 

Glad you figured it out.

 

I guess this is the reason why you dumped it and got the CLE 53?

 

Well, I didn't exactly "dump" my C43. It had almost 80,000 miles on it on it and was due for an upgrade. So, I traded it in for the "new and improved" CLE53.

I really liked the C43 but, as with a lot of cars these days, it wasn't without its foibles. The C43 trans was a little schizophrenic in normal driving but shifted great in Sport Modes, very quick and crisp shifts and it did a little double-clutch rev matching on downshifts. Pretty cool I thought. The exhaust sounded awesome. It really exemplified the dual nature of AMG. Relatively quiet under normal, flaps closed, operation and very rambunctious in Sport modes with the valves open. It had a real snap, crackle, pop! As I've said in the past, the first time I did a full throttle 1-2 upshift the crack was so loud that I thought a gun went off. Just what you'd expect from AMG. Today's AMG's, not so much. https://www.autoblog.com/news/merced...usts-get-quiet

Otherwise I'm very pleased with the CLE53. It looks great, especially with the big 295's in the rear. It's bigger/heavier than the C43 but it's got more tech, I love the new screen. It handles better, it's faster and quieter and gets almost as good mpg. Pretty much a win-win. The only issue it has is with the software that keeps turning off the Easy Entry/Exit button. MB will hopefully fix that soon. I'm on a mission to replace the mufflers to fix the exhaust "problem".

 

Thanks for your mini-review : ) I see, I understand now.

 

Did you consider an exhaust valve module first, as you already know the exhaust is not fully open even in sport+ mode, only at high RPMs. I mean downpipes is the way to go but maybe you will like the increased volume from the EVM first?

 

I heard about the EVM but how does it work? Is it s/w or some kind of mechanical override? Frankly, even at WOT the stock exhaust doesn't sound that great.

Regarding the Downpipe, it replaces the catalytic converter. I'm not going to consider that.



The car is plenty fast. Probably easier to add a JB4 or similer to get more power. Just add more boost. Turbocharging is great that way.

My goal is to address the immediate problem which is the mufflers by adding back a second muffled exhaust pipe from the passenger side muffler (just like earlier AMG'S). That should pick things up all by itself. If the new mufflers don't measure up with computer controlled flaps, I can always add the EVM.

 

I have my Easy Entry/Exit turned off because I have heard, at least on earlier cars, that the constant raising and lowering of the steering wheel can increase the wear and likelihood of a steering wheel electronics malfunction.

 

Yes the EVM overrides the ECU's control, it shouldn't trigger any code in the ECU or a CEL, it overrides the control and controls the flaps/actuator. By stock, the ECU likes to close it as tight as possible when not needed.

 

Good call, it is a very common failure too on earlier cars, the motor just stops working.

 

Both tilt electric motors are fine.

The jam is caused by an adjustment nut that gets super tightened during operation.

It's built to go bad in a hurry. Nut needs to be JB-Welded in place.

Thr extra trouble is when convenience is disabled, it does not move either during crash situation.

 

If it does get stuck, I heard that one method to unstuck it is to bang your knee on the bottom of the steering wheel while trying to electrically adjust it again?

 

... and then you get the loose SCM pins to act up with wild shifter.

Do not bang steering wheel at all unless you want more troubles.

Disable the poor tilt: it's designed to need endless repairs.