Auto Start/Stop engine function

[Robz26]

Hey team,

Apologies if this has been asked and answered, as I am mobile-only and can't search well.

Do you use the auto start/start feature? Why or why not?

I feel like a start must be worse on the engine by definition because of the sudden motion and startup routine... but I also know that "engine hours" matter as well as miles, so I'm torn.

Does it make a huge impact on MPH? I live in NYC so it certainly would be utilized often... however I also find the frequent starts a bit jarring.

Thoughts?

Rob

[kscarrol]

Never use it on the M3. Was fully aware of the gas mileage and was not a consideration when buying...

I did have my car in for routine maintenance today and the F30 328 loaner had auto start/stop activated so I left it on as I ran errands. Not a terrible feature as it seemed minimally invasive in city traffic, at least on the 328. Still, don't see myself using it on the M3.

The one thought that kept crossing my mind was the impact on the battery. These car already have battery issues related to insufficient charge related to start and stop driving patterns and short trips. I have to believe the start/stop feature would only make this situation worse with the starting and stopping in city. No proof to back that up just a concern based on my limited exprerience.

[Vic311]

No..i think its silly..and I suspect that over time it can hurt the longevity of the starter

[arsnlrob]

I do use it routinely (except in stop-go traffic). It took a couple weeks to get used to it, now I barely notice. There isn't much engine shutter when it starts back up, but you do hear the electric cranking sound. Overall pretty cool.

[mlhj83]

Originally Posted by Robz26

Hey team,

Apologies if this has been asked and answered, as I am mobile-only and can't search well.

Do you use the auto start/start feature? Why or why not?

I feel like a start must be worse on the engine by definition because of the sudden motion and startup routine... but I also know that "engine hours" matter as well as miles, so I'm torn.

Does it make a huge impact on MPH? I live in NYC so it certainly would be utilized often... however I also find the frequent starts a bit jarring.

Thoughts?

Rob

It definitely saves fuel, as to what the amount is depends on your driving. The engine/starter motor will not be damaged from frequent stop starts as their design has been taken into account for the stop/start system. There are a lot of criteria to satisfy before the system deems it suitable and safe to stop the engine. I for one like it, I know many others don't. I see no harm in gaining 1-2mpg with the system. It all adds up overtime.

[mlhj83]

Originally Posted by Vic311

No..i think its silly..and I suspect that over time it can hurt the longevity of the starter

The starter motor is different to the non-stop/start M3.

[Mr. ///M3 RD]

I used it once to try it out ... Then never again.

Feels strange to stand on a traffic light with an M3 and the engine off ...

[delta]

Originally Posted by M3RD

...Feels strange to stand on a traffic light with an M3 and the engine off ...

Agree. With due respect to all the responsible reasons why Auto Start/Stop is a good thing, a quiet M3 on the street is not what I signed up for....

[e92involved]

Nevr knew about this option. Wonder if my car has it, probably not if I am wondering. Is there a button somewhere for this? Thanks in advance.

[AshyLarryMP]

I use it sometimes, but I'm not convinced that it is good for the car. It doesn't seem like driving 100 mph on the freeway should be followed by the engine shutting off for 20 seconds and then starting up again.

I am more concerned about being good to the car than saving a few dollars on gas.

[AshyLarryMP]

Originally Posted by e92involved

Nevr knew about this option. Wonder if my car has it, probably not if I am wondering. Is there a button somewhere for this? Thanks in advance.

The button is above the ash tray. When you press the button the light turns off and enables stop/start. It came out in 2011.

[mamadub]

Originally Posted by M3RD

I used it once to try it out ... Then never again.

Feels strange to stand on a traffic light with an M3 and the engine off ...

+2

[GB///M3]

I think it's a pretty cool feature, but I never actually use it. I think in the long run it will harm the car even If the starter is different than cars without. I wonder if it wears the spark plugs out faster..

[Mike van D]

Don't use, once was enough for me after delivery. Little uncomfortable sitting there in traffic with engine off...immediately started thinking what if the darn thing doesnt restart.

[Mr. ///M3 RD]

Originally Posted by Mike van D

Don't use, once was enough for me after delivery. Little uncomfortable sitting there in traffic with engine off...immediately started thinking what if the darn thing doesnt restart.

Genau .... Translation ... Exactley + 10

[corrado79]

I use it and like it. I got used to it a couple years ago in Europe with a rental. It's common there. Once you get used to it, you start to dig it.

I enjoy long red lights now knowing I am letting her rest.

[FVM3]

i dont like it. I feel the "delay" when it starts again

[warranty]

My 08 doesn't have start-stop, but there are two major intersections on my daily commute where, if I had to wait for the green light, the wait is ALWAYS several minutes long. So, if I had start-stop, I would probably use it only at those two places and just disable it everywhere else. I know--I didn't buy my M3 for the fuel economy or to save the planet or anything, but why spew unnecessary hydrocarbons into the atmosphere when I *know* I'll be stopped for an "extended period" right?

[jaehshim]

Does it actually save fuel for the M3?
no, no and NO

This tech is plain silly for the M3 and we all know well that this is just a showoff annoyance for EPA standards.

I'd use that feature if i had a Toyota Camry (if they have the feature) as a daily Driver.

[mlhj83]

Originally Posted by jaehshim

Does it actually save fuel for the M3?
no, no and NO

This tech is plain silly for the M3 and we all know well that this is just a showoff annoyance for EPA standards.

I'd use that feature if i had a Toyota Camry (if they have the feature) as a daily Driver.

Erm, yes it does. Whether it's of significance to the owner is another matter. Based on my usage of a tank a week, and stop/start improving my economy by 1-2mpg (from my own experimentation), I would be saving approx. 3-4 tanks of fuel a year; insignificant to some, but if I can save, why not, it's a months worth of fuel at the end of the day.

[jonasaurus]

No idea how much it saves but I always hit the button to turn it off when I get in the car (UK cars have it set to default position on, need to get it coded off) along with the lock door button... It may not hurt the starter motor but I'm too old fashioned perhaps thinking it will, added to that I figure its a V8 so why try and save fuel.

[Rshane]

Don't like it. I keep it off. I tried it once just because I like to push buttons. With my Akrapovic exhaust it sounded like I was stalling the motor at each light. Besides, any benefit gained is usually quickly lost when I floor it from one light to the next.

I have been thinking about putting a Hybrid logo behind the M3 symbol just to mess with folks.