Start-stop system

[AndyJ]

There is a button to disable it . I am just wondering, is it better to disable or leave it on. I really like the functionality and ability to save petrol but am worried about the long run effects...

That button is only a temporary button. As soon as you turn the car off / on then it resets again ! :evil:

Unlike in America, where they all told BMW where to shove it and so once turned off it STAYS off.

 

[californiagirl]

E89's with auto gearbox don't have stop/start, at least mine doesn't anyway.

Strange! The F30 3 series (both 20i and 28i) have it, even with an auto box. And those are the same engines...

What year is yours? Mine is a 2012

Our F30 330d auto touring has it, don't tend to notice it, as does our zed (only a baby 2.0 manual). We have service packs on both so hoping that it is ok for the engines as they wouldn't want to be replacing things if it harms them.

 

[35isDreamer]

the pop of the exhaust in sports mode as the DCT goes through the gears is truly addictive! You'll love it!!

+1

Roof down this morning, hearing just that. Foot to the floor, change from second to third. Boom! Like a rocket.

 

[dr_john]

E89's with auto gearbox don't have stop/start, at least mine doesn't anyway.

Strange! The F30 3 series (both 20i and 28i) have it, even with an auto box. And those are the same engines...

What year is yours? Mine is a 2012

My E89 is a 2014 auto 20i, and doesn't have it. I previously had a 2012 manual 28i, which did have it

 

[Billy]

E89's with auto gearbox don't have stop/start, at least mine doesn't anyway.

Strange! The F30 3 series (both 20i and 28i) have it, even with an auto box. And those are the same engines...

What year is yours? Mine is a 2012

My E89 is a 2014 auto 20i, and doesn't have it. I previously had a 2012 manual 28i, which did have it

Weird! Out of interest, since you have both a 20i and a 28i, how do the engines compare in your opinions? I have driven the 28i engine in other Bimmers, but never in a Z4 - cracking engine! Although the Z4 is nice and light which is why the 20i seems to work nicely as well.

 

[AndyJ]

Although the Z4 is nice and light which is why the 20i seems to work nicely as well.

Nice and light ? Are we talking about the E89 here ? :wink:

 

[chasBMW]

the 3 series they lent me whilst my roof was being fixed was fitted with this feature , glad I only had it for 2 days because it drove me mental and as someone else mentioned off isnt off because everytime you restart it comes on again at the very least default setting should be other way round

 

[Billy]

Although the Z4 is nice and light which is why the 20i seems to work nicely as well.

Nice and light ? Are we talking about the E89 here ? :wink:

True... Let me rephrase... Relatively light due to the lack of rear seats and compared to some other 4 seater convertibles with a metal roof

 

[dr_john]

Weird! Out of interest, since you have both a 20i and a 28i, how do the engines compare in your opinions? I have driven the 28i engine in other Bimmers, but never in a Z4 - cracking engine! Although the Z4 is nice and light which is why the 20i seems to work nicely as well.

I tried out a 20i and decided that it was not sufficiently different fom the 28i to warrant the difference in cash (about £4.5k as I recall)

 

[techathy]

I tried out a 20i and decided that it was not sufficiently different fom the 28i to warrant the difference in cash (about £4.5k as I recall)

Interesting because for all intents and purposes the 28i engine should be like driving a 20i two gears lower most of the time. It is in a manual 3 series.

 

[Billy]

I tried out a 20i and decided that it was not sufficiently different fom the 28i to warrant the difference in cash (about £4.5k as I recall)

Interesting because for all intents and purposes the 28i engine should be like driving a 20i two gears lower most of the time. It is in a manual 3 series.

I'm not sure if you can compare to the 3... I have driven the F30 in both 328i and 320i versions. Those are the same engines which are in the 20i and 28i Z4s... I think the Z4 20i feels much quicker and more responsive than the 320i, probably due to the lower weight. Performance is thus also somewhere between the 320i and 328i.

Anyway, well off topic! How bad is the start-stop system really? Should one switch it off most of the time or leave it one (assuming it doesn't annoy)

 

[techathy]

I'm not sure if you can compare to the 3... I have driven the F30 in both 328i and 320i versions. Those are the same engines which are in the 20i and 28i Z4s... I think the Z4 20i feels much quicker and more responsive than the 320i, probably due to the lower weight. Performance is thus also somewhere between the 320i and 328i.

Increase power & torque 30% and you experience about 2 gears worth of extra acceleration, the weight of the vehicle is immaterial. Though while we are on weight, you are aware that the 320i & Z4 20i & 28i all tip the scales at around the 1500kg mark :wink:

Anyway, well off topic! How bad is the start-stop system really? Should one switch it off most of the time or leave it one (assuming it doesn't annoy)

Depends. If you end up in situations where you pause at junctions for a few seconds, then it'll be better turned off. If you cruise up to lights then sit there for longer (>20s) periods then you're probably better off leaving it on. I personally which I could have a 'pause' button on the engine because most of the time I want it off but at certain junctions I want it to turn on

 

[ronk]

It's disabled when the car is in gear / drive tho?
So if you are at a junction ready to move its all systems normal?

 

[techathy]

Not driven a BMW auto with stop start under a wide range of conditions but in a manual it's a right PITA. Pull up to a side junction, hand brake on, out of gear to stop sitting with your foot on the clutch and the engine cuts out. The second or so delay if it's a very short gap means you can't pull away in the space without pulling out a little too late .

OT: Talking of handbrake, is there any way to code in a hold assist/auto handbrake? A I drive has that and it's really nice as you pull to a stop, leave it in gear, make sure you're not touching the throttle & release the foot brakes. The car is held and to pull away you simply apply the throttle. Dealer didn't seem to think this was possible in the Z4

 

[ronk]

Not driven an auto with stop start under a wide range of conditions but in a manual it's a right PITA. Pull up to a side junction, hand brake on, out of gear to stop sitting with your foot on the clutch and the engine cuts out. The second or so delay if it's a very short gap means you can't pull away in the space without pulling out a little too late

But by the time you've stuck it into gear, it's started! I found the same with the auto, by the time it's into drive, the engines running - that not saying I like it you understand!

 

[techathy]

Starting & settling ready for deploying decent amounts of power took about 2-3s on my 120d (N47). This was the same on both the loaner 120ds I drove. If you tried to pull out sharpish with big throttle and a fairly snappy clutch close the engine would just bog down or even worse stall if you pulled out straight away, give it that extra second or two & it'd just launch down the road without issue.

The xDrive was great for getting out of a side road with DTC off. Launch out of a side road on the clutch and a fair amount of throttle, hook second and feed in the throttle at the same time. This would send you flying down the road & up to the NSL in record time

 

[Nictrix]

I would imagine that the system works the same as the Mini.
The engine does not cut out until you lift the clutch and its in neutral.
If you keep the clutch pedal pressed, even if its in neutral the engine will continue to run.
If you do lift the clutch and the engine cuts out as soon as you depress the clutch the engine starts again.
No idea how it would work in an auto though, maybe if you put it in park although who does that at a set of lights.

 

[techathy]

Mechanically sitting there with your foot on the clutch puts excessive load on the thrust bearing & a failed thrust bearing is a short cut to needing a new clutch in double quick time. Driving style wise it's not a good idea because it encourages clutch riding which is a great way to write off a clutch & puts a lot of load on the flywheel, with dual mass flywheels being less than 100% reliable to start with this is hardly a good thing.

I drove a fiat with a cable operated clutch for many years. The clutch cable had a tendency to snap randomly under load . While changing gear without the clutch is most definitely possible, makes for great rev matching practice, stalling the engine at every junction/traffic light & using the starter motor to pull away is hardly ideal.

 

[Billy]

It's disabled when the car is in gear / drive tho?
So if you are at a junction ready to move its all systems normal?

Yes. As soon as you put your foot on the clutch the engine starts up again.

Mechanically sitting there with your foot on the clutch puts excessive load on the thrust bearing & a failed thrust bearing is a short cut to needing a new clutch in double quick time. Driving style wise it's not a good idea because it encourages clutch riding which is a great way to write off a clutch & puts a lot of load on the flywheel, with dual mass flywheels being less than 100% reliable to start with this is hardly a good thing.

I drove a fiat with a cable operated clutch for many years. The clutch cable had a tendency to snap randomly under load . While changing gear without the clutch is most definitely possible, makes for great rev matching practice, stalling the engine at every junction/traffic light & using the starter motor to pull away is hardly ideal.

Interesting. Maybe it is just better then to keep the system off for most of the time and only really enable it when it makes sense.

 

[ronk]

A pal has just bought a new Ford with the system and he is turning it off on his busy stop and go run to work !

I would have thought that was the very time it was really needed?