darkh0rse

With all due respect, you are clueless to the issue at hand. The problem many of us are describing should not be confused with the typical characteristic changes that occur when you throw a car in sport mode. It's not a matter of hitting the throttle. In my case, the car will buck back and forth.. as in NOT accelerate. Let's put it this way, if you weren't wearing your seat belt and you attempted to "nail the throttle" your head would repeatedly smash into the steering wheel, while to the outside you would look like an amateur learning to drive stick for the first time. Mind you, not every time, just maybe 1 out of 10 times. Consider it Russian roulette with the GLC43.

As I mentioned, I had the foreman immediately tell me it's not normal when I was able to replicate the bucking with him in the car. Usually a dealership will do the opposite and try to tell you every thing the car is doing is part of the experience and working as intended but not this time. This is a serious problem. I've owned many new and used cars over and only my very first car (a 1989 Honda Accord with 300k+) felt more unsafe than this particular GLC43. I'm out of town now, but bringing the car back in July. I'm giving the dealership one more chance at resolving this issue before trading it in. I hate the fact I even have to think about trading in this car (will take a huge loss) but that should tell you how serious this problem is.

To anyone else trying to post about how this is part of sport+ mode, it's not. Some of us have experience driving and know the difference between what's normal and what's not.

wmc021

Hi darkHorse,

If you read my post it is my experience of when it has happened to me on a couple of occasions. I can now drive the car in sport + without it happening or if I choose too, can reproduce the jerk if required.

I'm not saying it is a good thing and I'm not saying it's not some type of fault or engine /gearbox mapping issue that may need some update. Yes you are quite right it is unnerving. But you can learn to avoid it when using Sport +.

Let's hope it is a fault that MB can sort.

darkh0rse

It's not avoidable. Not from my experience and I have tried countless times. I don't consider myself an amateur driver and drive all my cars aggressively and mostly in sport/sport+ settings. To me it doesn't sound like your GLC43 has the same problem. Consider yourself lucky. I've already had an update done on the car which didn't fix it. Not sure what the next recommended step will be until I bring it back in July. My patience is already on the low end since I custom ordered my GLC43 and waited 4 months to get it. To say I'm disappointed is an understatement. It's a shame they didn't use the same transmission as in the GLA45 which was 10x better from my experience. Just solving the bucking would make me happy but I'm not holding my breathe.

If anyone out there is having this issue and has had a dealership fix it then please chime in. Thank you.

stath

Does it shake when you floor it from a dead start?
If yes, it could be a drive shaft problem.

darkh0rse

No, it doesn't shake. It jolts/bucks (back and forth, back and forth, etc), harshly. Also, it doesn't happen every time but is common enough where I cannot consistently or safely drive it in sport+ mode.

I've pretty much decided not to keep this SUV. From the sounds of everyone with a similar problem there hasn't been a single person who has reported this fixed. It sucks to have to take the depreciation hit so early but life is too short to be driving in something I'm not going to enjoy. Sure, I can try and get it fixed but the dealer doesn't even have a clue what the problem is or why it's happening. Oh well.

wmc021

Have you tried a ECU reset.

Worth a go:

Turn the ignition key to the on (not start) position.

2. Press the gas pedal to the floor and hold for five seconds.

3. Turn the key to the "off" position (don't remove the key), then release the gas pedal.

4. Wait at least two minutes for ECU to reset.

decorily

Doesn't this reset the gearbox?

The auto gearbox "learns" your style /requirements of driving and AFAIK this procedure resets to default.

wmc021

Your correct I meant TCU

hhcheng23

I am C43 owner... completely the same issue happening. It is really dangerous when you have car behind you. I even feel scared whenever I have to accelerate from a stop.(not know if it will jerk this time...) I have invested a lot on this car(clear bra, mods....). Its too late for me to trade in. I swear I will push hard to get an answer and solution for this....

FYI, I am too native to think that a ECU tune would fix this...I went for stage 2 tuning, and the jerking is just getting even worse. Now it happens more often than before, even in Comfort mode and gear 2.
However, looking at the dyno sheet, I am guessing the jerking is caused by the sudden torque pulse. If they can smooth the curve probably there is a hope.

decorily

Thankfully I haven't experienced this issue with my 250d.

I have however experienced something similar with my previous car...a VW Touareg. This was a manual transmission and occasionally I got what I could only describe as 'uncontrolled bucking' when accelerating from a near stop in 2nd gear. What I had to do was momentarily release the accelerator and resume acceleration again.

As described earlier in this thread it was similar to what a learner driver might encounter while moving away in a manual transmission. I however haven't fallen into the learner category in decades!

darkh0rse

Sorry to hear you're having this issue.

I've since traded in my GLC43. To my dealerships credit, they gave me the full amount back minus a few hundred bucks for the mileage. I then picked up a brand new 2017 CLS550 with a 10% discount in magnetite black. It's a bit more expensive but the v8 is very smooth and powerful. No bucking or jolting, given this car doesn't have a sport+ mode but at least it's as fast if not faster than the GLC43.

I think anyone picking up a car with the 43 moniker needs to be careful. I don't think Mercedes has done their due diligence on this setup.

hhcheng23

My C43 has 4.5k miles on it plus I have invested $4k+ on clearbra, tuning, mods...etc. Kind of too late for trade it back, but its always an option.
What was the milage when you trade back? Do you have to pay sales tax again?

darkh0rse

I had low mileage, 1700 km. I paid the difference minus a few bucks. I think I paid sales tax but I also got sales tax back. That said, I made my dealership aware of the issue within the first week. I was also able to replicate it with the foreman in the car whom agreed something was up. I did have about $2,000 of xpel on mine so I did take a loss there but I'd rather do that than drive a faulty SUV. You must have wrapped your entire car at that price point which obviously makes it harder to justify a trade now. I feel for ya. Hopefully they come up with a fix at some point.

tkc_hawaii

I'm having the same issue, and it's a violent bucking, without exaggeration. Mercedes engineers test drove 2 new C43's and a GLC 43, and the same issue occurred, one very violent. The problem progressively became worse for me. After one software update, it became worse yet. Case escalated to Germany, another update, and problem still exists. Was told I would essentially need to be on a racetrack to utilize the sport and sport + modes. This is an AWD C Class "sedan" with some added muscle - we are putting our families in these vehicles and one should be able to drive in any mode without unsafe complications. I purchased the vehicle as my primary transportation, and to drive in sport plus mode - and should be able to do so, without being thrown into the dash. Has this problem been rectified for anyone?

glassbloke

So with my GLC 43 on it's way to a ship, is this a problem with everybody's GLC? I know that the ones who are having the problem are commenting here but is there anyone who has not experienced this problem?

dieseldoc

I think these blogs are a place where people come for information or to complain. I think the majority of owners never ever come near these blogs and are happy with their cars.

ble2716

I have a GLC43 and I do not have this problem.
I always wait for the engine warmed up before I put it in Sports+ mode.
Does it help? Maybe, maybe not.

quikag

Happened to my wife on a test drive of a GLC43. Car was in Sport plus mode. I gave her crap for bad throttle application.

Sad thing is, we placed an order for an '18 GLC 43 Coupe today. MB better fix this before our car arrives in December....My wife and I plan to use Sport plus frequently to enjoy the AMG exhaust option we selected.

Honestly, this sounds like a safety issue that MB better fix ASAP.

darkh0rse

Yea, cause some of us have nothing better to do than "complain" about a safety/performance issue that has no known fix as of yet. How about, just maybe, some of us have done our due diligence and have found a legitimate issue to bring forth, or, as you would like to put it, "complain" about. Get real. Most people won't know this problem exists because most don't drive in sport+ and since it's an intermittent issue it will go unnoticed or will be written off for a long time before Mercedes does anything about it. I wouldn't be surprised if we see a recall down the line. This is why it's important to "complain" when there is an actual problem. No one should have to deal with something not working as intended, or worse yet, a safety issue on a brand new car from any company, let alone a car company like Merecdes. There I go complaining again, my bad.

darkh0rse

You're basically rolling the dice and hoping that A) they are aware of the exact problem B) they care enough to fix it and C) there is an actual easy fix that can be implemented quick enough.

Maybe you'll get lucky and get one of the 43 variants without the problem. Good luck.

Bribritheguy

Same issue here. Jerking episode once. Another possibly different issue was a misfire. She went to like 30% power after a misfire on the highway and started shaking during a pass. Continued to shake under soft acceleration. Happened once in Sport+ then again in comfort with only like 70% throttle. It was on my first road trip. Conditions were warm, had been driving for a couple hours. Only goosed it every 20-30 mins. Had to pull over and turn off the car after finding a safe place on the house GMH way. Very scary. Took it to the dealer after both episodes, said it was a misfire and cleared the code. Going to pick it up tomorroe after and update. I can't believe I'm researching lemon laws in Illinois after 3,500 miles on a 5 month old car. Will keep you guys posted.

Konak88

Hi all. First post here and I picked up my 2018 GLC43 on Black Friday. Just hit 1k miles so decided to try out sport+ today and experienced the exact same violent jerking while accelerating from a stop. Jerk violently three times. I did accelerate a little more aggressively than normal since I figured that’s what sport+ is meant for.
Just wondering if anyone has any updates that has experienced this issue and if you ever got it resolved. TIA

mike7ee

Not on my '18 GLC300.

I even drove around today as slow as possible around my street stopping/starting in S+, nothing but normal behavior.
Obviously didn't see it my test drives either.

Might be a AMG 43 issue?

ajmtbm

i had a 2017 had a similar issue. when i was slowing down if i then hit gas to accelerate it would get a little jerky. Brought it in they did a software update and now it is gone.

ajgraham

This is one of the best descriptions of this problem in Sport+. To expand on it the issue would be as follows for the most common scenario I encounter:

1. You're approaching a corner that requires braking.
2. You apply brakes, car changes down gears.
3. You're coasting around the corner (not accelerating or braking) at around 10mph.
4. You start accelerating normally, low throttle.
5. If within 1-2 seconds of this initial acceleration you even lift off the accelerator 1mm the car jerks back massively, as if you've just hit the brake.

I don't think the gearbox has changed gears at stage 4/5. The gearbox is quite rough anyway, in any mode you can get occasional sharp gear changes out of nowhere. I'll try and get the software updated and see.