Herky Jerky

[milk242]

My car use to be super jerky. I've either become a better pedal modulator or the transmission ecu has learned my behavior.

[ellipsis212]

Search landed me in this thread. I've experienced this a few times since buying the car last week and it's my first DCT (or auto of any type for that matter). I've noticed that it happens in Sport Plus engine/manual mode/trans 2 when I'm not totally committing to the throttle, both in 1-2 but also once in 2-3 which was sketchy as I was already going 30mph.

It feels like the car doesn't want to be in Sport Plus unless I'm caning it or that the traction control is interfering somehow. Interested to hear others' thoughts.

[Who's on first]

Originally Posted by ellipsis212

Search landed me in this thread. I've experienced this a few times since buying the car last week and it's my first DCT (or auto of any type for that matter). I've noticed that it happens in Sport Plus engine/manual mode/trans 2 when I'm not totally committing to the throttle, both in 1-2 but also once in 2-3 which was sketchy as I was already going 30mph.

It feels like the car doesn't want to be in Sport Plus unless I'm caning it or that the traction control is interfering somehow. Interested to hear others' thoughts.

I rest my adaptations again. All has been great for the last 1,500 miles.

Maybe try that.

[Wah]

Both my E92 dct and F82 dct were jerky, especially when cold and on sport or sport+ in first gear. Shift to 2nd early if it starts to buck.

It is honestly one of the reasons I'm going with 6MT on my 2nd F82.

[ellipsis212]

Originally Posted by Who's on first

I rest my adaptations again. All has been great for the last 1,500 miles.

Maybe try that.

Reset the adaptations this morning and couldn't get it to buck off the start in S+ so I'm hoping that helped. I've also learned to shift into 2nd a little earlier when being forced to start gently due to traffic.

[M3Comet]

I have a similar issue in my 2013. More noticeable when cold, but still there when warm. Interestingly, if I conduct a slow and smooth acceleration with constant throttle position, while in manual mode (mine does it in second gear), the jerkiness is gone.
So to me, the problem lies with DCT/engine computer and how it accelerates the car in normal drive mode.
Has anyone here tried to replicate the issue in manual mode vice drive, or the other way around?

[G4BR13L]

It is basically a manual gearbox with a double clutch so yes in lower gears this is normal.

[M3Comet]

Originally Posted by G4BR13L

It is basically a manual gearbox with a double clutch so yes in lower gears this is normal.

But it's different in manual mode to auto mode. Mine is 'jerkier' in auto mode.

[danchee]

It jerks in "edge cases" as those in software calls it. Typically when the engine is cold and you're going into situations where you're in between gears or you start accelerating out and just as it is about to up switch someone cuts you off and you let off on the accelerator but didn't hit the brakes hard as that someone was going fast enough to give you enough space to reaccelerate. That back and forth causes DCT to engage clutch, dis-engage, and immediately tries to up switch again.

[LDRM3]

My car 2018 M3 violently bucks back and forth giving it gas, from a stop...it gets locked up and once it starts the car becomes uncontrollable....meanwhile cars are passing me on one side..honking from behind...terrible, truly a safety issue for me and other drivers near me...embarassing, and frustrating.

[M3Comet]

Originally Posted by LDRM3

My car 2018 M3 violently bucks back and forth giving it gas, from a stop...it gets locked up and once it starts the car becomes uncontrollable....meanwhile cars are passing me on one side..honking from behind...terrible, truly a safety issue for me and other drivers near me...embarassing, and frustrating.

Try moving your foot higher up on the accelerator pedal, so your heel is at the base of the pedal, and stabilise your foot against the sidewall. You can actuate the throttle with much more finesse and will stop it most times. Worked for me.

[LDRM3]

My car 2018 M3 violently bucks back and forth giving it gas, from a stop...it gets locked up and once it starts the car becomes uncontrollable....meanwhile cars are passing me on one side..honking from behind...terrible, truly a safety issue for me and other drivers near me...embarassing, and frustrating.

[Beemerm3]

Originally Posted by LDRM3

My car 2018 M3 violently bucks back and forth giving it gas, from a stop...it gets locked up and once it starts the car becomes uncontrollable....meanwhile cars are passing me on one side..honking from behind...terrible, truly a safety issue for me and other drivers near me...embarassing, and frustrating.

Lol u need control over ur car. 1st is rough for beginners.

[shortseller]

Originally Posted by LDRM3

My car 2018 M3 violently bucks back and forth giving it gas, from a stop...it gets locked up and once it starts the car becomes uncontrollable....meanwhile cars are passing me on one side..honking from behind...terrible, truly a safety issue for me and other drivers near me...embarassing, and frustrating.

As said above, get your entire foot on the gas peddle helps a lot. Problem is as you start off going forward the initial force just tends to pull your foot off the gas. You need to keep constant pressure down while getting starts. Also helps to keep your seat adjusted close enough to keep your entire foot engaged. All this and practice will cut down on the jerking back and forth. Manual seems to also be less susceptible as well.

[Beat RickC]

My M4 stopped being herky jerky once I started using my toes and ball of my foot. The experience of accelerating from a dead stop in DCT is MUCH more enjoyable in S or S+.
, now.
For some reason placing my foot flat caused the problem. Granted the problem mainly showed up on a bumpy or undulating street.

[mcc3456]

Originally Posted by Who's on first

Mine is always in 2nd gear. A few times it has actually moved me/seat forward and aft. I'm seriously starting to wonder if I have an actual issue.

EDIT: Happens in any and all settings.

My 2015 was the same exact way, until dealer reset adaptations, which solved the problem for about 4-6 months, then would do it all the time again, until reset again. After the 4th or 5th service visit, I ended the lease a year early, and just bought the Alfa Giulia Quadrifoglio. Shifts nearly as fast in Race Mode and is a hell of a lot smoother. Honestly, felt the M3’s DCT kind of sucks compared to all other DCTs I’ve driven, and another one I currently own. Was the biggest thing I hated about my M3, aside from the random frequent Driver Assistance Freak outs and unexpected iDrive reboots. YMMV though.

[shortseller]

Originally Posted by mcc3456

My 2015 was the same exact way, until dealer reset adaptations, which solved the problem for about 4-6 months, then would do it all the time again, until reset again. After the 4th or 5th service visit, I ended the lease a year early, and just bought the Alfa Giulia Quadrifoglio. Shifts nearly as fast in Race Mode and is a hell of a lot smoother. Honestly, felt the M3’s DCT kind of sucks compared to all other DCTs I’ve driven, and another one I currently own. Was the biggest thing I hated about my M3, aside from the random frequent Driver Assistance Freak outs and unexpected iDrive reboots. YMMV though.

An update software change should have helped a lot. My ‘18 CP has little to no herky jerky unless I kind of force it on by coming off the gas after a quick start which confuses the dct. BTW, It acts a lot like a manual in that respect. Once floored and keeping constant peddle pressure makes for a very smooth gear change in sport or sport+.

[hellokitty]

I noticed that if I turn the DCT down from S3 to S2, the jerky throttle response is gone. Pedal input seems to be better modulated in the S2 setting. I’ve always ran in S3 on the street and I can’t believe it took me 30k miles to figure this one out lol

[mfurse]

If you position your ankle on the hinge point of the accelerator and use the full range of motion of your foot to accelerate there is more control and less likelihood of "kangarooing" when taking off.

[Silverlining_m2]

On the rare occasion that I undulate the gas pedal in 1st accelerating from a light, as soon as it starts to "kangaroo", I just shift to 2nd. Easy peasy

[Ejones4541]

Originally Posted by F82spaceship

On the rare occasion that I undulate the gas pedal in 1st accelerating from a light, as soon as it starts to "kangaroo", I just shift to 2nd. Easy peasy

I was getting to post the same thing…let off the accelerator long enough for it to recover and get back in it I'm a controlled manner -or- shift to 2nd and then retrace what lead to it then learn from what lead up to it…it's not the car, it's the driver…and I can say that because I've had the same thing happen to me.

[appa_808]

It usually happens in 2nd gear for me in S+ once in a blue moon. I can kinda feel it right before it's about to happen so I try to keep my foot stable on the throttle and just shift up to 3rd gear.