Automatic Start/Stop

doccyber · 11-21-2016, 08:10 PM

How much gas one really saves with this? Specially since it puts too much strain on the starter and I'm sure this leads to premature wear of the starter. Thx

DF · 11-21-2016, 08:16 PM

I'm sure some. I don't use it

B_Rice · 11-21-2016, 09:44 PM

It can save you a considerable amount depending on your commute. Besides, since all of our motors are direct injection it doesn't take much to turn the motor back on. (guesstimating half a crank or less?) I personally don't use mine since it sounds stupid to have a performance car with a loud exhaust turning on and off in traffic.

ianp622 · 11-22-2016, 08:24 AM

Some reports say 5-7% improvement in economy, this real-world test with a BMW showed 9% for city driving: http://www.edmunds.com/bmw/3-series-...ings-test.html

EuroDude · 11-22-2016, 08:36 AM

I remember test driving my 235 and it turned off at a light. I was like, WHAT!!?? Salesman told me to push the button above the start button to disable it and I actually bought that car. It's been disabled ever since. However, I have a new 2016 Malibu company car and it CANNOT be disabled....I hate it, total POS.

Sportstick · 11-22-2016, 08:59 AM

Turned it off on day #1. Learned that it will stay off as long as I am in Comfort, Sport, or Sport+, but using Eco will turn it back on. That's easy enough. The potential savings are minimal, but offset for me by whatever incremental wear/tear the multiple restarts creates. No matter how well the car was engineered for increased durability to handle the restarts, the wear will be reduced by not experiencing them.

Fabspeed Motorsport · 11-22-2016, 09:05 AM

It actually does not put as much strain on the starter as you think. The amount of turn it needs to turn back on is equivalent to a 1/4 crank. Also the car needs to meet a handful of requirements for it to shut off, so it won't shut off every single time you come to a stop.

Along with the Auto Start/Stop feature, BMW's Efficiency Dynamics claim up to 20% fuel savings. I assume this would be EcoPro Mode with all other fuel saving features enabled.

Maynard · 11-22-2016, 09:17 AM

I turned mine off from delivery. Early on I accidentally hit the button w/o realizing it and turned it on. Nearly had a fit at the next light, thinking that the subtle shudder it makes coming on was the guy behind me hitting me as the light turned (as usual, he found it irresistible to be driving as close as possible for several blocks, and was right up my butt at the light). Fortunately I figured it out as I was pulling away (the early months were basically learning to relax and assume that unexpected stuff was the car being smarter than me, unless there was an explicit warning message).

geep81 · 11-22-2016, 10:17 AM

In my Mercedes it did not actually restart the engine using the starter at a stop/start. It had some way of firing a cylinder that was closest to some point if I remember right, and it didn't use the starter at all. I'd imagine this is a similar case with the BMW but I never checked it out because I too usually leave it disabled.

bimmerfile · 11-22-2016, 02:56 PM

Quote:

Originally Posted by doccyber

How much gas one really saves with this? Specially since it puts too much strain on the starter and I'm sure this leads to premature wear of the starter. Thx

Jeebus, you live in the states - why even think about the eyedropper full of gas you could save per day using auto S/S?

doccyber · 11-22-2016, 04:48 PM

Quote:

Originally Posted by bimmerfile

Quote:

Originally Posted by doccyber

How much gas one really saves with this? Specially since it puts too much strain on the starter and I'm sure this leads to premature wear of the starter. Thx

Jeebus, you live in the states - why even think about the eyedropper full of gas you could save per day using auto S/S?

My point exactly. The cost of starter will be more than the gas saved.

overcoil · 11-22-2016, 05:04 PM

Quote:

Originally Posted by bimmerfile

Jeebus, you live in the states - why even think about the eyedropper full of gas you could save per day using auto S/S?

A lot of it is urban emissions - which in turn is directly related to fuel consumption. I guess theoretically they feel in ten or fifteen years when a larger % of vehicles on the road have and use start/stop...

If I'm in my car somewhere where there are lots of people, or a mom with a baby stroller I'll turn on the start/stop feature

MZWIE · 11-22-2016, 05:27 PM

This whole thing came about so manufacturers could show better numbers for CAFE. Other than that it is totally worthless.

overcoil · 11-22-2016, 05:34 PM

Quote:

Originally Posted by e34m5

This whole thing came about so manufacturers could show better numbers for CAFE. Other than that it is totally worthless.

And cafe standards in the past decade weren't due to oil embargo, there's an element of emissions ? I'm not even sure fuel dependency is the issue more like climate change ?

Rayscott · 11-22-2016, 07:07 PM

Quote:

Originally Posted by e34m5

This whole thing came about so manufacturers could show better numbers for CAFE. Other than that it is totally worthless.

I agree, it is annoying.

Deutsche-Broke · 11-22-2016, 07:49 PM

Quote:

Originally Posted by e34m5

This whole thing came about so manufacturers could show better numbers for CAFE. Other than that it is totally worthless.

I Agree completely.. Appease the tariff collectors..

*grumble grumble grumble*

xantdieselx · 11-22-2016, 07:56 PM

I guess I'm in the minority as I don't mind it. I use it a lot especially in stop & go traffic. I would think it lowers the overall emissions footprint as well. I think it's a good thing.

ianp622 · 11-23-2016, 07:06 AM

Are we certain it actually uses the starter? BMW had a direct injection method in 2012 for auto start/stop that didn't use the starter. Given the N55 and B58 are both direct injection I don't know why they wouldn't make use of that method and avoid most wear issues.

Maynard · 11-23-2016, 07:54 AM

I'd not heard of this, thought it was all via the starter (but a bigger one, that can do that re-gen thing to recoup engine braking energy for the charging tasks). The idea of constantly firing a static piston has me wondering if this is trading bearing/piston life for starter life. Seems like the worst case scenario for piston scuffing and harsh bearing loads on the fired-cylinder. Any engineers who can weigh in?

shil · 11-23-2016, 08:56 AM

Leaving your car at home is best for wear and tear.
The auto-stop doesn't bother me. Big deal.

JohnnyCanuck · 11-23-2016, 10:05 AM

Quote:

Originally Posted by xantdieselx

I guess I'm in the minority as I don't mind it. I use it a lot especially in stop & go traffic. I would think it lowers the overall emissions footprint as well. I think it's a good thing.

+1 ... I only use it for stop and go, but for the same reason.

Merc for hire · 11-23-2016, 10:44 AM

Auto start saves me some gas, which comes out of my pocket, so I use it.
If the starter breaks, warranty covers it. The car will be returned in 3 years anyway.

11-21-2016, 08:10 PM	#1
doccyber Captain 269 Rep 630 Posts Drives: %D0%97%D0%B0%D1%81%D1%82%D0%B0 Join Date: Oct 2015 Location: Los Angeles, CA iTrader: (0)	Automatic Start/Stop How much gas one really saves with this? Specially since it puts too much strain on the starter and I'm sure this leads to premature wear of the starter. Thx
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11-21-2016, 08:16 PM	#2
DF Major 244 Rep 1,255 Posts Drives: F23 Join Date: Sep 2013 Location: Sherman Oaks iTrader: (0)	I'm sure some. I don't use it
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11-21-2016, 09:44 PM	#3
B_Rice Lieutenant 225 Rep 518 Posts Drives: 6spd Estoril Blue M235i Join Date: Mar 2016 Location: Los Angeles iTrader: (0)	It can save you a considerable amount depending on your commute. Besides, since all of our motors are direct injection it doesn't take much to turn the motor back on. (guesstimating half a crank or less?) I personally don't use mine since it sounds stupid to have a performance car with a loud exhaust turning on and off in traffic. __________________ Estoril Blue 6spd M235i LSD Sunroof delete AWE touring exhaust Fabspeed sport cat
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11-22-2016, 08:24 AM	#4
ianp622 Private First Class 52 Rep 117 Posts Drives: 2017 M240i Join Date: Jul 2016 Location: FL iTrader: (0)	Some reports say 5-7% improvement in economy, this real-world test with a BMW showed 9% for city driving: http://www.edmunds.com/bmw/3-series-...ings-test.html
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11-22-2016, 08:36 AM	#5
EuroDude Second Lieutenant 68 Rep 201 Posts Drives: 2017 GT350 Join Date: May 2016 Location: Florida iTrader: (2) Garage List 2017 Ford GT350 [0.00]	I remember test driving my 235 and it turned off at a light. I was like, WHAT!!?? Salesman told me to push the button above the start button to disable it and I actually bought that car. It's been disabled ever since. However, I have a new 2016 Malibu company car and it CANNOT be disabled....I hate it, total POS.
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11-22-2016, 08:59 AM	#6
Sportstick Major General 6348 Rep 7,250 Posts Drives: '15 228i and '24 X3 sDrive30i Join Date: Mar 2014 Location: Southwest USA iTrader: (0)	Turned it off on day #1. Learned that it will stay off as long as I am in Comfort, Sport, or Sport+, but using Eco will turn it back on. That's easy enough. The potential savings are minimal, but offset for me by whatever incremental wear/tear the multiple restarts creates. No matter how well the car was engineered for increased durability to handle the restarts, the wear will be reduced by not experiencing them. __________________ 2015 228i 6MT/Track Handling/Tech/Cold/Premium/Lighting/Driver Assistance/KCDesign Strut Brace/M2 LCA&Tension Strut w/Powerflex Bushings/Rogue SSK/17" BBS SR/ExtremeContact Sport02/ER Chargepipe/AA Intercooler/Dinan Shockware/MPerf Spoiler/Black Grilles/Xpel Ultimate PPF & Prime XR+ Tint/no CDV 2024 X3 sDrive30i/MSport/Premium/Dynamic Handling/Shadowline/Parking/Xpel Prime XR Plus
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11-22-2016, 09:05 AM	#7
Fabspeed Motorsport 1022 Rep 1,653 Posts Drives: BMW M235i Join Date: May 2015 Location: Fort Washington, PA iTrader: (0)	It actually does not put as much strain on the starter as you think. The amount of turn it needs to turn back on is equivalent to a 1/4 crank. Also the car needs to meet a handful of requirements for it to shut off, so it won't shut off every single time you come to a stop. Along with the Auto Start/Stop feature, BMW's Efficiency Dynamics claim up to 20% fuel savings. I assume this would be EcoPro Mode with all other fuel saving features enabled.
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11-22-2016, 09:17 AM	#8
Maynard Brigadier General 5601 Rep 3,251 Posts Drives: 228iX & M2C Join Date: Mar 2016 Location: Upstate NY iTrader: (1)	I turned mine off from delivery. Early on I accidentally hit the button w/o realizing it and turned it on. Nearly had a fit at the next light, thinking that the subtle shudder it makes coming on was the guy behind me hitting me as the light turned (as usual, he found it irresistible to be driving as close as possible for several blocks, and was right up my butt at the light). Fortunately I figured it out as I was pulling away (the early months were basically learning to relax and assume that unexpected stuff was the car being smarter than me, unless there was an explicit warning message).
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11-22-2016, 10:17 AM	#9
geep81 Private First Class 47 Rep 102 Posts Drives: 2016 M235xi Join Date: Nov 2015 Location: Cleveland iTrader: (0)	In my Mercedes it did not actually restart the engine using the starter at a stop/start. It had some way of firing a cylinder that was closest to some point if I remember right, and it didn't use the starter at all. I'd imagine this is a similar case with the BMW but I never checked it out because I too usually leave it disabled.
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11-22-2016, 05:27 PM	#13
MZWIE Lieutenant Colonel 422 Rep 1,661 Posts Drives: M2 Join Date: Jun 2007 Location: GEORGIA iTrader: (0)	This whole thing came about so manufacturers could show better numbers for CAFE. Other than that it is totally worthless.
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11-22-2016, 07:56 PM	#17
xantdieselx Kingslayer 417 Rep 1,481 Posts Drives: 25 BMW M2 Join Date: Jun 2008 Location: RI iTrader: (0)	I guess I'm in the minority as I don't mind it. I use it a lot especially in stop & go traffic. I would think it lowers the overall emissions footprint as well. I think it's a good thing. __________________ Previous Cars: 2008' 135i, 2010' 328i, 2013' 328i, 2016' M235i, 2017' X1, 2019' M240i, 2019' X3, 2021' M3 Comp, 23' Camaro SS 1LE, 24' Lexus IS500 Current Cars: 23' Tesla Model Y Performance, 11' BMW 335I. Coming Soon: 25' BMW M2 Manual
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11-23-2016, 07:06 AM	#18
ianp622 Private First Class 52 Rep 117 Posts Drives: 2017 M240i Join Date: Jul 2016 Location: FL iTrader: (0)	Are we certain it actually uses the starter? BMW had a direct injection method in 2012 for auto start/stop that didn't use the starter. Given the N55 and B58 are both direct injection I don't know why they wouldn't make use of that method and avoid most wear issues.
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11-23-2016, 07:54 AM	#19
Maynard Brigadier General 5601 Rep 3,251 Posts Drives: 228iX & M2C Join Date: Mar 2016 Location: Upstate NY iTrader: (1)	I'd not heard of this, thought it was all via the starter (but a bigger one, that can do that re-gen thing to recoup engine braking energy for the charging tasks). The idea of constantly firing a static piston has me wondering if this is trading bearing/piston life for starter life. Seems like the worst case scenario for piston scuffing and harsh bearing loads on the fired-cylinder. Any engineers who can weigh in?
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11-23-2016, 08:56 AM	#20
shil Huh? Wazzat? 32 Rep 41 Posts Drives: 228i xDrive Join Date: Oct 2016 Location: Hamilton, ON iTrader: (0)	Leaving your car at home is best for wear and tear. The auto-stop doesn't bother me. Big deal.
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11-23-2016, 10:44 AM	#22
Merc for hire First Lieutenant 157 Rep 387 Posts Drives: M235i 6MT Join Date: Mar 2015 Location: Toronto, Ontario, Canada iTrader: (0)	Auto start saves me some gas, which comes out of my pocket, so I use it. If the starter breaks, warranty covers it. The car will be returned in 3 years anyway.
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