THE LARGEST BMW 2-SERIES FORUM ON THE PLANET
2Addicts
2Addicts
BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read
2Addicts | BMW 2-Series forum BMW 2 Series (F22) Forum BMW 2 Series Coupe and Cabriolet (F22/F23) General Forum Random 1st gear stutter/stumble with 6MT

Post Reply
 
Thread Tools Search this Thread
      08-27-2016, 12:07 AM   #1
XutvJet
Major General
5488
Rep
5,334
Posts

Drives: 2011 Cayman Base, 2016 M235
Join Date: Mar 2016
Location: Kansas City

iTrader: (-1)

Random 1st gear stutter/stumble with 6MT

I've owned my 2016 M235 6mt for a bit over 6 months and 6k miles. I've been driving manuals for decades and have always found the 6MT in this car difficult to drive smoothly under normal driving when in Sport+ or Sport with the aggressive throttle mapping. Lately I've been driving around in DSC Off and i much prefer the linear throttle and the lack of nanny intervention. WOT 1-2 and 2-3 shifts feel much better and shifting at part throttle is much smoother and easier to modulate.

Anyway, for the past two weeks or so since I've been driving in DSC Off, I've noticed a very random stumble/stutter as I'm leaving the light normally in 1st. The stumble seems to happen just as I'm releasing the clutch fully in 1st at a very slow speed. The feels like accelerator pedal goes dead for a split second and the acceleration pauses momentarily. It lasts not even a second but it's still felt and is rather annoying. Even more annoying is how random it is. It might happen once a day. I never feel in Sport+ or Sport with the aggressive throttle mapping. Perhaps it's somewhat masked by the overly quick throttle. The issue isn't even worth noting to the dealer because it's so random right now. All other driving situations are fine. The car has no modifications.

Anyone else experience this? Is this possibly the CDV?
Appreciate 0
      08-27-2016, 06:46 AM   #2
redontheline
Second Lieutenant
redontheline's Avatar
70
Rep
222
Posts

Drives: EB 235 MT
Join Date: Jan 2016
Location: NJ

iTrader: (0)

Maybe going to friction too quickly? I am not certain I'm understanding where you are feeling this from but I am still not perfect with this clutch on low speed acceleration leaving 1st, especially after 2 months in the shop. I typically get some bounce or stutter as the clutch engages and I attribute it to my timing being off and having no rev hang compared to the Civic.
Appreciate 0
      08-27-2016, 05:35 PM   #3
XutvJet
Major General
5488
Rep
5,334
Posts

Drives: 2011 Cayman Base, 2016 M235
Join Date: Mar 2016
Location: Kansas City

iTrader: (-1)

I thought that at first too, but it doesn't feel quite like that. It really feels like the throttle dies for a split second rather than releasing the clutch too quickly and causing a momentary bog.

I do find the clutch take up to be quite wonky in this car, meaning the clutch has a ton of travel for initial engagement but the point it fully engages is quite narrow. I find this rather annoying around town, but during aggressive driving and on launches, it works really well.
Appreciate 0
      08-27-2016, 06:26 PM   #4
overcoil
Major General
3069
Rep
5,577
Posts

Drives: M235i 6spd
Join Date: Dec 2013
Location: Mid-Atlantic

iTrader: (0)

After getting familiar with the 235 over many months, I sometimes blip the throttle twice gently when releasing the clutch into first gear and taking off.

Then, as someone pointed out recently, you can almost take off on first gear (and reverse) with just the clutch and no throttle, so I apply gas near the end of when I let up off the clutch, but sometimes out of nowhere, when it feels like I'm doing everything right, I get clutch judder on a takeoff.
Appreciate 0
      08-27-2016, 08:51 PM   #5
3.0L
Colonel
3.0L's Avatar
8902
Rep
2,011
Posts

Drives: M235i, 20k miles
Join Date: Apr 2014
Location: California

iTrader: (0)

Flaky clutch disc? This has happened to me in some of my previous manual transmission cars. One needed a new clutch disc every 10k miles to keep it smooth. And no, I did not abuse, ride or excessively slip the clutch.
__________________
///M235i | Mineral Grey Metallic | Premium Package | Technology Package | Driver Assistance Package | Dakota Coral Red/Black Leather | Harman/Kardon Premium 360 watt sound system | 8-speed automatic

When writing your life's plan, use a pencil with an eraser
Appreciate 0
      08-27-2016, 08:59 PM   #6
amw896
Major
amw896's Avatar
Canada
583
Rep
1,117
Posts

Drives: 2015 BMW M235i
Join Date: Feb 2016
Location: ontario

iTrader: (0)

Garage List
2015 BMW M235i  [10.00]
Quote:
Originally Posted by 3.0L
Flaky clutch disc? This has happened to me in some of my previous manual transmission cars. One needed a new clutch disc every 10k miles to keep it smooth. And no, I did not abuse, ride or excessively slip the clutch.
come on!? 10k miles with no abuse? what car?
Appreciate 0
      08-31-2016, 06:42 PM   #7
BMW335iOn18s
Resident BMW Fanboy
BMW335iOn18s's Avatar
United_States
259
Rep
866
Posts

Drives: F82 CS SMB
Join Date: Jul 2007
Location: Philadelphia, PA

iTrader: (0)

Hey, this is normal, my car is the same, and i think we have a similar driving style.

My theory is this is how BMW limits torque at low RPMs so that clutch life is preserved. The expectation is that most drivers will slip the hell out of the clutch. (You'd be surprised how many europeans slip the clutch more than necessary).
__________________
Current: '20 F82 M4cs SMB / '13 640i M-Sport Carbon Black
Past: F30 330xi Luxury Line / F22 M235i 6MT / E92 335i / E46 330ci / E36 328i 5MT
Appreciate 0
      08-31-2016, 09:14 PM   #8
raleedy
Colonel
United_States
160
Rep
2,248
Posts

Drives: 2016 228i 6-speed
Join Date: Jul 2005
Location: Portland, Oregon

iTrader: (0)

Quote:
Originally Posted by ScottSinger View Post
After getting familiar with the 235 over many months, I sometimes blip the throttle twice gently when releasing the clutch into first gear and taking off.

Then, as someone pointed out recently, you can almost take off on first gear (and reverse) with just the clutch and no throttle, so I apply gas near the end of when I let up off the clutch, but sometimes out of nowhere, when it feels like I'm doing everything right, I get clutch judder on a takeoff.
These turbo-charged engines offer little or no torque at idle, so that "tip-in" has to be managed carefully. The computer will not let the engine revs drop down from drag as you engage the clutch, provided you do it gradually. Get ahead of the computer a little, though, and you get exactly what you describe. One nice surprise: push the clutch pedal back in, and Auto Start/Stop gets you going again seamlessly, as if nothing had happened. Unless you've shut it off, of course.
Appreciate 0
      09-01-2016, 12:22 AM   #9
XutvJet
Major General
5488
Rep
5,334
Posts

Drives: 2011 Cayman Base, 2016 M235
Join Date: Mar 2016
Location: Kansas City

iTrader: (-1)

Quote:
Originally Posted by raleedy View Post
These turbo-charged engines offer little or no torque at idle, so that "tip-in" has to be managed carefully. The computer will not let the engine revs drop down from drag as you engage the clutch, provided you do it gradually. Get ahead of the computer a little, though, and you get exactly what you describe. One nice surprise: push the clutch pedal back in, and Auto Start/Stop gets you going again seamlessly, as if nothing had happened. Unless you've shut it off, of course.
Try driving a WRX if you want to experience a turbo car with no torque off idle or in the low rpms. In normal driving, my M235 feels like a diesel coming off the line compared to my prior 2012 WRX LOL.

For the past few days I've been driving around solely in Sport+ and the car never had a low rpm hick up. I'm starting to think what I was experiencing in the non-aggressive throttle modes is a factor of a cold engine, the CDV delay, and/or some odd throttle tuning factor. The quicker throttle apparently gets around this issue simply because the throttle is quicker perhaps skates past this glitch.

Like as noted before, these cars don't require much throttle to get going and starting out in 2nd on any sort of decline or even a 2mph roll is easy. With my WRX, i had to use 1st far more.
Appreciate 0
      09-01-2016, 12:23 AM   #10
XutvJet
Major General
5488
Rep
5,334
Posts

Drives: 2011 Cayman Base, 2016 M235
Join Date: Mar 2016
Location: Kansas City

iTrader: (-1)

Quote:
Originally Posted by BMW335iOn18s View Post
Hey, this is normal, my car is the same, and i think we have a similar driving style.

My theory is this is how BMW limits torque at low RPMs so that clutch life is preserved. The expectation is that most drivers will slip the hell out of the clutch. (You'd be surprised how many europeans slip the clutch more than necessary).
Agreed.
Appreciate 0
      09-02-2016, 09:41 AM   #11
BillD1953
Lieutenant
232
Rep
417
Posts

Drives: 2018 X3 M40i
Join Date: Dec 2015
Location: Portsmouth NH

iTrader: (0)

10K on my new 2016 228i 6MT....never really noticed what the OP experiences getting into 1st....I feel the typical clutch shutter like I do with all MTs.

I drive mostly in Comfort mode...I'll switch on to Sport+ and "feel" what he's stating about
Appreciate 0
      09-03-2016, 11:51 PM   #12
murderwasthebass
Private
murderwasthebass's Avatar
United_States
31
Rep
79
Posts

Drives: 2016 228i Coupe, M Sport, 6MT
Join Date: Jan 2016
Location: Silicon Valley, CA

iTrader: (0)

Garage List
When I'm starting off in first, I always tap the throttle just a little bit to where you can feel the engine "shake" and then I slowly release the clutch at that point. Works fairly well for me.
__________________
-Christopher
Appreciate 0
      10-26-2016, 03:26 PM   #13
XutvJet
Major General
5488
Rep
5,334
Posts

Drives: 2011 Cayman Base, 2016 M235
Join Date: Mar 2016
Location: Kansas City

iTrader: (-1)

I thought I'd update this thread after nearly two months. This issue is clearly caused by the internal clutch delay valve (CDV). By being a bit slower and careful with my clutch foot, I don't experience the issue.

Another thing, running a clutch stop seems to negatively impact around town drivability as well. I ran a homemade 3/16" thick clutch stop for quite a while to reduce the clutch throw and engagement point. Apparently the CDV and self-adjusting clutch mechanism do not like you running a clutch stop. I had become annoyed with how much I had to "think" when trying to get a smooth start with the Sport throttle mapping. It was often a very slight bog or a bit to rapid. The 1-2 shift could be a little jerky too. I've been driving manuals for decades and found this car to be by far the hardest to leave the line smoothly when trying to leave at a moderate pace. Turns out the clutch stop was the problem. I removed that last week and all the modulation issues disappeared. I guess I ran the clutch stop for so long that I forgot how the car drove prior.
Appreciate 0
      10-26-2016, 06:58 PM   #14
Y0tsuya
Second Lieutenant
77
Rep
261
Posts

Drives: 2015 M235i 6MT, 2016 340i 8AT
Join Date: Jun 2015
Location: SF Bay Area

iTrader: (0)

Don't know if it's related but with a cold engine and ASS on, the car would sometimes almost stall itself getting off the line. No problem after it warms up.
Appreciate 0
      10-26-2016, 10:12 PM   #15
wjones14
Captain
wjones14's Avatar
640
Rep
878
Posts

Drives: 2021 M2C
Join Date: Oct 2014
Location: Niantic CT

iTrader: (0)

Quote:
Originally Posted by XutvJet View Post
I thought I'd update this thread after nearly two months. This issue is clearly caused by the internal clutch delay valve (CDV). By being a bit slower and careful with my clutch foot, I don't experience the issue.

Another thing, running a clutch stop seems to negatively impact around town drivability as well. I ran a homemade 3/16" thick clutch stop for quite a while to reduce the clutch throw and engagement point. Apparently the CDV and self-adjusting clutch mechanism do not like you running a clutch stop. I had become annoyed with how much I had to "think" when trying to get a smooth start with the Sport throttle mapping. It was often a very slight bog or a bit to rapid. The 1-2 shift could be a little jerky too. I've been driving manuals for decades and found this car to be by far the hardest to leave the line smoothly when trying to leave at a moderate pace. Turns out the clutch stop was the problem. I removed that last week and all the modulation issues disappeared. I guess I ran the clutch stop for so long that I forgot how the car drove prior.
I agree with you about the M/T being more difficult than most to drive smoothly.

But I don't see the clutch stop as being a negative. I thought the factory clutch travel was excessive, so I took BentZero's tip and bought the $10 Burger Tuning clutch stop - best cheap mod ever! I removed one of the washers because there was no free play before engagement with all of them. With the removed washer it grabs maybe 1 to 1-1/2 inches from the floor. About the same engagement point as my Mini with no clutch stop.
__________________
Vehicles: 2021 Alpine White M2C 6MT; 2011 Kawasaki Z1000 (1/4 mile 10.3 seconds @ 129 mph - stock)
Previous: 2018 Camaro 2SS 1LE 6MT; 2015 BMW M235i 6MT; 2015 Mini Cooper F56 6MT; 2005 Mustang GT 5MT; 2003 Mini Cooper R50 5MT
Appreciate 0
      10-27-2016, 09:53 AM   #16
XutvJet
Major General
5488
Rep
5,334
Posts

Drives: 2011 Cayman Base, 2016 M235
Join Date: Mar 2016
Location: Kansas City

iTrader: (-1)

Maybe my car or foot are different. I'm far smoother leaving the line and on shifts without any sort of clutch stop in place. I can more easily gauge the friction point and range. I do agree that the clutch throw is excessive.
Appreciate 0
      10-27-2016, 11:24 AM   #17
Mobil
New Member
7
Rep
18
Posts

Drives: 2014 M235i - Alpine White
Join Date: Mar 2015
Location: Ottawa

iTrader: (0)

I share your pain too...I've only ever driven stick, and after 30000 kms...I'm still stuttering this car off the line...

Doesnt help that the Throttle mapping differs between the modes, and I change my shoes often between work dress shoes, runners, boots all contributing to me occasionally looking like a rookie at stoplights...
Appreciate 0
      10-27-2016, 12:08 PM   #18
JoyRin
Private
22
Rep
66
Posts

Drives: 2015 EB M235i manual
Join Date: Sep 2015
Location: South Jersey

iTrader: (0)

Mine does as well. Only when the car is warm. It chatters as i release the clutch. If i do my normal rpm when getting going in 1st gear (~1k rpm), it'll go thud-thud-thud as im releasing the clutch. If i give it a little more rpms (~1.5k rpms) it'll thud usually just once before it fully engages. Everyone says dual mass flywheel is the cause. Considering im hearing a lot of people with similar issues, i think im inclined to believe it and just live with it.
Appreciate 0
      10-27-2016, 04:34 PM   #19
XutvJet
Major General
5488
Rep
5,334
Posts

Drives: 2011 Cayman Base, 2016 M235
Join Date: Mar 2016
Location: Kansas City

iTrader: (-1)

Quote:
Originally Posted by Mobil View Post
I share your pain too...I've only ever driven stick, and after 30000 kms...I'm still stuttering this car off the line...

Doesnt help that the Throttle mapping differs between the modes, and I change my shoes often between work dress shoes, runners, boots all contributing to me occasionally looking like a rookie at stoplights...
Yep to all of that. You either leave the line at a snail's pace, carefully engaging 1st or you fly off the line. It's really hard to find that middle ground, but without the clutch stop, I'm far more consistent. Maybe BMW intended the 6MT to drive this way so as to sway us towards 8AT and DCTs automatics (tin foil hat on)

I will say that launching this car hard is very easy. I can really feel that line between a fractional amount of spin and avoiding bogging.
Appreciate 0
      10-28-2016, 12:14 AM   #20
savethemanuals
Enlisted Member
United_States
16
Rep
41
Posts

Drives: '16 M235i 6-speed
Join Date: Mar 2016
Location: Philadelphia, PA

iTrader: (0)

Quote:
Originally Posted by JoyRin View Post
Mine does as well. Only when the car is warm. It chatters as i release the clutch. If i do my normal rpm when getting going in 1st gear (~1k rpm), it'll go thud-thud-thud as im releasing the clutch. If i give it a little more rpms (~1.5k rpms) it'll thud usually just once before it fully engages. Everyone says dual mass flywheel is the cause. Considering im hearing a lot of people with similar issues, i think im inclined to believe it and just live with it.
When you say chatters, what exactly do you mean? This thread seems to be talking about power (I don't experience that, launches are pretty smooth for me) but every time I take off in this car the engine makes this awful clicking sound, and also only when it's warm. It sounds like the engine wants to stall. Anyone else had that happen?

(By the way, I'm not just letting the clutch out and allowing the engine to shake...This happens even when I rev to about 1200 and slowly let the clutch out while maintaining revs)
Appreciate 0
      10-28-2016, 11:55 AM   #21
jase2addict
Private First Class
United_States
16
Rep
120
Posts

Drives: 2021 M2Comp
Join Date: Jun 2016
Location: Los Angeles

iTrader: (0)

My 230i is at the dealer now. I was having rough shifts and the car was shaking at start up and idle. Made the car feel cheap. I have a BMS clutch stop on the way and I plan to change to motul oils when I hit 1500 miles. Hopefully that will help the shifting. The foreman and I went for a ride and he said that is how the BMW shits, i.e. CVD mechanism. I guess I was expecting a bolt action precision shift. I'll keep you guys posted on what they say.
Appreciate 0
      10-29-2016, 09:46 AM   #22
thehalcyon
Second Lieutenant
Canada
52
Rep
248
Posts

Drives: '12 135i MT LeMans
Join Date: Nov 2012
Location: Ottawa, Canada

iTrader: (0)

I have the same thing OP describes in 135i , at first I thought it was a missfire or sparkplug related, changing the plugs improved it but it's never fully gone away. I just blip the throttle a bit taking off and it's my work around. Annoying but several techs have test drove my car and not noticed anything out of the ordinary so I assumed it was just my driving habits.
Appreciate 0
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 03:09 AM.




2addicts
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST