2012 S350 BlueTec - Rough transmission on initial acceleration, dealer runaround?
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2012 S350 BlueTec
2012 S350 BlueTec - Rough transmission on initial acceleration, dealer runaround?
I am new to this forum, so sorry if this has been covered elsewhere. I have a 2012 S350 BlueTec diesel with 30K miles. I have noticed recently that when I accelerate slowly from a dead stop, the car has a slight jolt when changing gears. It doesn't happen all the time, but often enough that I took it to my local dealer. After keeping it a few days, I was told that the jolt was a "feature" of the diesel powertrain that puts the car into neutral when it's idle for a certain period of time (to save gas), and the jolt I was feeling was the transmission moving back to 1st gear when I accelerated. I was told this was a feature of the diesel engine transmission (something they called the KID transmission) and was assured this was normal. I'm skeptical that MB would engineer a car that has such a rough initial acceleration, especially a luxury model that cost over $100K new. Has anyone else experienced this issue with an S350? And more importantly does anyone have a recommendation on how I should proceed to get this fixed with MB? Thank you in advance for any help!
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S350 BT 4MATIC
I am new to this forum, so sorry if this has been covered elsewhere. I have a 2012 S350 BlueTec diesel with 30K miles. I have noticed recently that when I accelerate slowly from a dead stop, the car has a slight jolt when changing gears. It doesn't happen all the time, but often enough that I took it to my local dealer. After keeping it a few days, I was told that the jolt was a "feature" of the diesel powertrain that puts the car into neutral when it's idle for a certain period of time (to save gas), and the jolt I was feeling was the transmission moving back to 1st gear when I accelerated. I was told this was a feature of the diesel engine transmission (something they called the KID transmission) and was assured this was normal. I'm skeptical that MB would engineer a car that has such a rough initial acceleration, especially a luxury model that cost over $100K new. Has anyone else experienced this issue with an S350? And more importantly does anyone have a recommendation on how I should proceed to get this fixed with MB? Thank you in advance for any help!
Last edited by Nuru; Sep 17, 2015 at 06:47 AM.
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I am new to this forum, so sorry if this has been covered elsewhere. I have a 2012 S350 BlueTec diesel with 30K miles. I have noticed recently that when I accelerate slowly from a dead stop, the car has a slight jolt when changing gears. It doesn't happen all the time, but often enough that I took it to my local dealer. After keeping it a few days, I was told that the jolt was a "feature" of the diesel powertrain that puts the car into neutral when it's idle for a certain period of time (to save gas), and the jolt I was feeling was the transmission moving back to 1st gear when I accelerated. I was told this was a feature of the diesel engine transmission (something they called the KID transmission) and was assured this was normal. I'm skeptical that MB would engineer a car that has such a rough initial acceleration, especially a luxury model that cost over $100K new. Has anyone else experienced this issue with an S350? And more importantly does anyone have a recommendation on how I should proceed to get this fixed with MB? Thank you in advance for any help!
one solution is to backflash the tcu to older code which seems does not have this feature.
let me know if you find a solution.
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S350 BT 4MATIC
alz, what version is the latest tcu code?
roliver, how long does the car have to be stopped before the transmission shifts into neutral, did the dealer tell you this?
Seems like this is a crappy update for saving a couple of miles per gallon? They might as well give everyone the ECO mode and be done with it.
roliver, how long does the car have to be stopped before the transmission shifts into neutral, did the dealer tell you this?
Seems like this is a crappy update for saving a couple of miles per gallon? They might as well give everyone the ECO mode and be done with it.
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2012 S350 BlueTec
Thanks for the responses. Nuru, the dealership said it will engage this feature after the vehicle is stopped for 4-5 seconds .. they call it "power free" mode. I agree its a crappy update. Alx have you talked to your dealership about a solution?
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S350 BT 4MATIC
Definitely not a good update. Once I find out what version of software, Hopefully they fix that in the next version. Seems strange as if you put the car into neutral/park and then switch to D or first gear, it does not do this?
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2012 S350 BlueTec
Good question Nuru .. I've never noticed it when I first put the car into D, only once I have been driving it and then stop. Btw I did send an inquiry into MBNA and will let you know what I hear back. Thank you!
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S350 BT 4MATIC
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S350 BT 4MATIC
Yes, hopefully that will happen if it is the latest software version that has surfaced or established the issue.
Last edited by Nuru; Sep 19, 2015 at 12:35 PM.
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2012 S350 BlueTec
Still waiting for a response from MBUSA. Received a response on 9/18 from a customer service rep saying that someone from their Produce Advice Dept would be back to me within 24 hrs .. but have not heard back yet. I sent a follow up email today.
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2012 S350 BlueTec
Well I heard back from MBUSA today, the Product Advice Dept. Unfortunately they confirmed what the dealership told me. This a "feature" of the 4MATIC meant to save fuel and limit vibration in the cabin (?). I was told it wasn't due to any recent software update though .. that it was original to the car (I purchased this car 6 mos ago so can't speak to what it drove like new). They suggested a 'work-around' ... basically use the paddle shifters each time I come to a stop to re-engage the transmission .. not something I'm likely to do every time I come to a stop. Was also told that only the Diesels had the feature at this time ... strange considering they already get much better mileage than the Gas versions. Totally unacceptable in my mind, but not sure what else I can do at this point other than tell the rest of the MB community to complain to MB until they fix it.
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2012 S350 BlueTec
kaqy, is this related to the S350 transmission issue in this post? Sorry, but sounded like it might have been posted to the wrong thread. If it's related, did this fix the issue?
