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 Brake Pedal vs Auto Stop/Start

Post Reply
 
Thread Tools Search this Thread
      05-11-2015, 12:30 AM   #1
bacampbe
Lieutenant
342
Rep
530
Posts

Drives: 2024 Z4 M40i PB
Join Date: Jun 2012
Location: Dallas, TX

iTrader: (0)

Brake Pedal vs Auto Stop/Start

I notice some differences in brake pedal behavior between my M235i vert and my wife's 328i:

When the auto start/stop kills the engine, I have to release the brake all the way to restart it. On the 328i, I just have to reduce pressure a hair. On the m235i, this means that the engine is usually not yet running when I first apply throttle.

Also, when creeping forward while riding the brake (e.g. while easing slowly into a parking place), the engine will sometimes stop while the car is still in motion. When this happens, there's a noticeable lurch when the thrust cuts out. This never happens on the 3er.

So, I wonder if there's a brake pedal sensor that is calibrated differently on the M235i? If this exists, is it adjustable?
Appreciate 0
      05-11-2015, 01:11 AM   #2
moldcad
Major
moldcad's Avatar
Poland
258
Rep
1,095
Posts

Drives: M235i
Join Date: Jan 2013
Location: Poland

iTrader: (0)

I don't know an answer to the second part of your question, but from your description it's your wife's 328i whose Start/Stop work properly with the gas pedal. My M235i works exactly the same, as did my previous BMW with the Start/Stop system (F10).
__________________
previous: 2003 E46 330i SMG
just sold: 2013 F10 528i xDrive
my AWD beater: 2015 Golf R mk7 DSG
my RWD pirate & long-distance cruiser: 2015 M235i AT8, LSD
Appreciate 0
      05-11-2015, 05:02 AM   #3
culinarymatt87
New Member
2
Rep
13
Posts

Drives: nissan juke digt 4x4 everyday
Join Date: Jan 2015
Location: uk

iTrader: (0)

Quote:
Originally Posted by bacampbe View Post
I notice some differences in brake pedal behavior between my M235i vert and my wife's 328i:

When the auto start/stop kills the engine, I have to release the brake all the way to restart it. On the 328i, I just have to reduce pressure a hair. On the m235i, this means that the engine is usually not yet running when I first apply throttle.

Also, when creeping forward while riding the brake (e.g. while easing slowly into a parking place), the engine will sometimes stop while the car is still in motion. When this happens, there's a noticeable lurch when the thrust cuts out. This never happens on the 3er.

So, I wonder if there's a brake pedal sensor that is calibrated differently on the M235i? If this exists, is it adjustable?
sport mode it job done
Appreciate 0
      05-11-2015, 09:25 AM   #4
casper83
Second Lieutenant
casper83's Avatar
119
Rep
221
Posts

Drives: M235i XDrive
Join Date: Jan 2015
Location: Wisconsin

iTrader: (1)

My M235i acts similar to your wife's car. I start to release the brake pedal and the car restarts.
Appreciate 0
      05-11-2015, 09:30 AM   #5
bacampbe
Lieutenant
342
Rep
530
Posts

Drives: 2024 Z4 M40i PB
Join Date: Jun 2012
Location: Dallas, TX

iTrader: (0)

I don't know if this is related, since it involves pressing rather than releasing the brake, but I also notice that I have to tap harder than I expect to deactivate the cruise control. In my wife's car, just a tiny tap will do it, but in mine I have to give it a conscious effort.

(On the flip side, I like the brake feel much better in the M235i. The 328i feels way too soft for my tastes. Hopefully the two are not related.)
Appreciate 0
      05-11-2015, 01:47 PM   #6
OpenAir
Captain
OpenAir's Avatar
United_States
431
Rep
887
Posts

Drives: Enzo F23 228i
Join Date: May 2015
Location: MD, USA

iTrader: (1)

Garage List
2015 BMW 228i  [0.00]
If I change the pressure on my break pedal my car starts back up....
Appreciate 0
      05-11-2015, 01:55 PM   #7
bacampbe
Lieutenant
342
Rep
530
Posts

Drives: 2024 Z4 M40i PB
Join Date: Jun 2012
Location: Dallas, TX

iTrader: (0)

Sounds like mine is miscalibrated. Anyone know how the start/stop system senses brake pedal position, and if there's something that can be adjusted?
Appreciate 0
      05-11-2015, 03:39 PM   #8
Pyewacket69
Second Lieutenant
Pyewacket69's Avatar
76
Rep
288
Posts

Drives: 2014 M235i
Join Date: Apr 2015
Location: South Carolina USA

iTrader: (0)

I would assume it keys off of the same circuit that enables the car brake lights.

Easy enough to check with an assistant watching the brake lights while the driver eases up on the brake pedal...
Appreciate 0
      05-11-2015, 06:15 PM   #9
bladeomatic
Lieutenant
bladeomatic's Avatar
United_States
115
Rep
418
Posts

Drives: 2018 M3 ZCP
Join Date: Mar 2014
Location: Los Angeles

iTrader: (0)

Quote:
Originally Posted by OpenAir View Post
If I change the pressure on my break pedal my car starts back up....
Ditto.

I also noticed a subtle thing:

I'm in Eco or Comfort noodling around in traffic.
I pull up to a stop light and come to a complete stop (engine shuts off)
I gently lift brake pressure or move a foot or two (engine restarts).
If I press down on the brake pedal again (full stop) the engine stays on and will not turn off again.

So in short, if shut down occurs and then restarts again quickly, it will not shut down again at the same stop.

It sort of makes sense...as if you're creeping into an intersection about to turn left. You don't want to have it turn off on you.
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 05:58 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