MCT Slipping on gear changes
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From: Phoenix
2012 C63 AMG Coupe
MCT Slipping on gear changes
Hey guys looking for some input here on 2012 coupe. So basically when the car is in any mode with traction on/sport it will “slip” and catch when I’m under partial throttle. And by slip I mean the rpms will jump up 300-600 and then it catches and goes, it’s the most noticeable when I’m crushing and I give it a little extra throttle to speed up (not enough to downshift to lower gear). It does it in 3-5, but it’s possible I don’t notice it in the lower gears cause of the ratios in the MCT. Under full throttle/load it doesn’t seem to do it.
I have tried the TCU reset, and disconnected my battery for 24 hours, both have done nothing to fix this.
The car is going into the dealer on Monday, but was hoping to see if anyone else had similar issues and the outcome.
TIA.
I have tried the TCU reset, and disconnected my battery for 24 hours, both have done nothing to fix this.
The car is going into the dealer on Monday, but was hoping to see if anyone else had similar issues and the outcome.
TIA.
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From: Montreal, QC
E55 AMG & C63 AMG
Mine is a little slippy sometimes on the 3-4 shift. This is under partial load, simply cruising. I just hit 50k KM's and am planning on changing the tranny fluid soon. We will see if that solves it.
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From: Phoenix
2012 C63 AMG Coupe
And I wondered if that has something to do with it. I will ask the dealer. I just want to go in with as much info as possible. The car currently has 54k miles on it.
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From: Miami, FL
2003 CL 600
Sounds like the torque converter/clutch is slipping if it's when you describe, only at lighter pressures. Agree on checking fluid first.
If you have a harsh shift from P-R-D (garage shift), the issue is usually with the gear position sensor in the conductor plate. Common failure item on the 722.9 still.
If you have a harsh shift from P-R-D (garage shift), the issue is usually with the gear position sensor in the conductor plate. Common failure item on the 722.9 still.
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From: Phoenix
2012 C63 AMG Coupe
Originally Posted by ItalianJoe1
Sounds like the torque converter/clutch is slipping if it's when you describe, only at lighter pressures. Agree on checking fluid first.
If you have a harsh shift from P-R-D (garage shift), the issue is usually with the gear position sensor in the conductor plate. Common failure item on the 722.9 still.
If you have a harsh shift from P-R-D (garage shift), the issue is usually with the gear position sensor in the conductor plate. Common failure item on the 722.9 still.
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From: Phoenix
2012 C63 AMG Coupe
Ok so an update. The car went to the dealer. They ran all their diagnostics and updates the software in the trans, but the car is still slipping. They can’t find anything wrong. They basically told me to keep driving the car as it is and come back if something comes up. I’m kinda at a loss on this one. The only other thing that I mentioned to them was that someone on the forums had suggested using DAS to reteach the “kiss point” on the clutch. The shop Forman thought that that wouldn’t make a difference so he suggested that I not spend the money to do it.
Any thoughts???
Any thoughts???
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From: Boston
2012 c63
Ok so an update. The car went to the dealer. They ran all their diagnostics and updates the software in the trans, but the car is still slipping. They can t find anything wrong. They basically told me to keep driving the car as it is and come back if something comes up. I m kinda at a loss on this one. The only other thing that I mentioned to them was that someone on the forums had suggested using DAS to reteach the kiss point on the clutch. The shop Forman thought that that wouldn t make a difference so he suggested that I not spend the money to do it.
Any thoughts???
Any thoughts???
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From: Phoenix
2012 C63 AMG Coupe
Yes, they reset the adaptations, and did a software update. The “kiss point” relearn is something different. From what I read it’s when the clutch engages the gear. I will make a video of what the car is doing and post it.
Last edited by Tlnt60; Oct 26, 2017 at 02:15 PM.
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W204 C63 Coupe, W166 ML350 BlueTEC, 928GT, Taycan GTS Sport Turismo, C5 Z06 & IS300 race cars
Here's another possibility - you tuned it with a more aggressive, snappy tune that over the course of two years has now worn down the MCT clutches to the point where you're starting to notice some slip... 
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2012 C63
I have a 2012 with about 50k miles and have been trying to track down what I think is the same issue. My car is 100% stock. Trans fluid changed at 40k.The best way I can recreate the situation is putting the car in Manual 5th gear at around 1800 rpm and then give it 10% throttle increase. The rpms will jump to 2200 and then back to 1800 before the car accelerates. If I drive aggressively, it does not happen. Can’t detect any “slip” at full throttle acceleration. That makes me think it is not true clutch slip, but rather the computer being “confused” and maybe not getting cam timing correct. That is a guess as I don’t really have any idea what the computers are doing. It just feels more like a “VTech” change gone bad than a physical problem. Sorry for the Honda reference...
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From: Phoenix
2012 C63 AMG Coupe
Originally Posted by mwetter
I have a 2012 with about 50k miles and have been trying to track down what I think is the same issue. My car is 100% stock. Trans fluid changed at 40k.The best way I can recreate the situation is putting the car in Manual 5th gear at around 1800 rpm and then give it 10% throttle increase. The rpms will jump to 2200 and then back to 1800 before the car accelerates. If I drive aggressively, it does not happen. Can’t detect any “slip” at full throttle acceleration. That makes me think it is not true clutch slip, but rather the computer being “confused” and maybe not getting cam timing correct. That is a guess as I don’t really have any idea what the computers are doing. It just feels more like a “VTech” change gone bad than a physical problem. Sorry for the Honda reference...
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2012 C63
Not yet. I read elsewhere about a similar situation that was solved by correcting the amount of trans fluid. Evidently, the fill until it flows out method can be wrong if the car is not perfectly level and you end up too low on fluid once the car is on the ground. I am going to test that theory as it seems simple and cheap.
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From: London, UK
W212 - E63 AMG
Any of you any closer to solving this one?
I've noticed with the recent freezing weather here, the tranny really doesn't like being cold and it needs loads of revs to get the car to move either in D or R, off the driveway and out onto the roads for several minutes. I normally baby the car anyway during this period, but after that, it's fine.
Have a I just answered my own question, or am I seeing some age-related symptoms because it just doesn't seem like to like being woken up at freezing temps? (0 degree's C)
I've noticed with the recent freezing weather here, the tranny really doesn't like being cold and it needs loads of revs to get the car to move either in D or R, off the driveway and out onto the roads for several minutes. I normally baby the car anyway during this period, but after that, it's fine.
Have a I just answered my own question, or am I seeing some age-related symptoms because it just doesn't seem like to like being woken up at freezing temps? (0 degree's C)
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From: Miami, FL
2003 CL 600
Any of you any closer to solving this one?
I've noticed with the recent freezing weather here, the tranny really doesn't like being cold and it needs loads of revs to get the car to move either in D or R, off the driveway and out onto the roads for several minutes. I normally baby the car anyway during this period, but after that, it's fine.
Have a I just answered my own question, or am I seeing some age-related symptoms because it just doesn't seem like to like being woken up at freezing temps? (0 degree's C)
I've noticed with the recent freezing weather here, the tranny really doesn't like being cold and it needs loads of revs to get the car to move either in D or R, off the driveway and out onto the roads for several minutes. I normally baby the car anyway during this period, but after that, it's fine.
Have a I just answered my own question, or am I seeing some age-related symptoms because it just doesn't seem like to like being woken up at freezing temps? (0 degree's C)
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From: London, UK
W212 - E63 AMG
Hmmm....see, I had all 8 solenoids replaced for new 2 years ago/~10k miles ago...surely it can't be the solenoids. The fluid therefore is also pretty recent.
I think i'll just take it out for a drive now and see how I feel about it as the car warms up and I'll report back. I want to get a bigger final drive gear programmed into the tranny, but i don't want to do that if the tranny is about to die on me. Hmm...
I think i'll just take it out for a drive now and see how I feel about it as the car warms up and I'll report back. I want to get a bigger final drive gear programmed into the tranny, but i don't want to do that if the tranny is about to die on me. Hmm...
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From: Phoenix
2012 C63 AMG Coupe
So an update on the car.
Took it to the dealer and turned out to be a bad valve body. They replaced it and as they were setting the adaptations they also noticed a IM vacuum leak (common issue). They are finishing up the car and I will pick it up today. Luckily my 3rd party warranty covered everything expect the fluids so total out of pocket is $330.
Took it to the dealer and turned out to be a bad valve body. They replaced it and as they were setting the adaptations they also noticed a IM vacuum leak (common issue). They are finishing up the car and I will pick it up today. Luckily my 3rd party warranty covered everything expect the fluids so total out of pocket is $330.
