[Katin]

I really wanted this feature to be of benefit and gave it a fair chance for the first 3 months of ownership. What I observed is a rough restart and a little confusion while sitting in traffic and inching along.
I did NOT see any appreciable improvement on mpg at all.
Lastly I believe that with the direct injection carbon issue it is only going to make things worse by shutting off a lot while all that hot gas is swirling around the top of the engine. Yes idling too can add to carbon build up but cold engine operation and frequent stop start is worse in my opinion.

[PappyVR4]

I don't see increased carbon buildup being an added issue with ASS. The bigger potential problem in my mind is a shortened starter lifespan. For such little gains, and also being an annoyance, it's not worth it.

[KGB_123_99]

I may be the only one on this forum who likes ASS (ha ha). There is something nice about sitting at a long red light in total peace and quiet.

I was never troubled by the engine restart. Yes, it is a bit rough but you get used to it. The 4 cylinder does it better than the 6. I can't say there is hesitation though. The engine starts before I have time to move my foot from the brake to the gas. It does force you to change your driving habits a bit as you can no longer creep in traffic. My biggest annoyance now is people who stop 30 feet behind a car at a light and then decided to pull up.

I wouldn't worry about longevity unless your engine shuts down 100 times in a day.

[chiefneil]

ASS will be more useful when it's integrated with traffic lights and apps like waze. For example I'd be happy to use it if it only kicked in when I stopped at a light that had 1 minute or more of wait time.

But when it kicks in during stop and go traffic, or a creeping line at a stop sign, or highway onramp metering lights, it's just plain annoying. It's on and off every 5s. Those instances are really the reasons I keep it disabled.

Maybe in about 20 years all those systems (traffic lights, waze/google maps/etc) will be integrated so systems like ASS will work better. Actually I'll probably be reading forums while my self-driving car chauffers me, which would be even better.

[wilbur_the_goose]

It's so easy to disable it in stop and go traffic. Takes what, 1 second to press the button?

[XRAVE]

Originally Posted by Katin

I really wanted this feature to be of benefit and gave it a fair chance for the first 3 months of ownership. What I observed is a rough restart and a little confusion while sitting in traffic and inching along.
I did NOT see any appreciable improvement on mpg at all.
Lastly I believe that with the direct injection carbon issue it is only going to make things worse by shutting off a lot while all that hot gas is swirling around the top of the engine. Yes idling too can add to carbon build up but cold engine operation and frequent stop start is worse in my opinion.

I think the added MPG benefit isn't for the end user as much as it is for the whole.

Let's assume 100,000 people, they each drive 20 miles per day and get 20 MPG. Those 100,000 people now use ASS and get 20.5 miles. As a whole, they could now travel 50,000 more miles using the same amount of gas.

If they weren't using ASS and only got 20 MPG instead of the increased 20.5 MPG, driving an additional 50,000 miles as a group would use up 2500 gallons of gas per day.

So that small increase of .5 MPG saves almost 1 million gallons of gas a year. Mind you this is assuming a very small increase in MPG, some studies show 10-12% which would make the savings as much as 6 million gallons a year.

I'm not sure how many people use ASS and only 95% sure my math was correct

[oneway]

I've owned 3 other vehicles with this feature and none of them were great. Seems like the feature might work better in a hybrid vehicle application.

[Billfitz]

Originally Posted by KGB_123_99

I may be the only one on this forum who likes ASS

I have no issues with it.

It does force you to change your driving habits a bit as you can no longer creep in traffic.

I do, no problem. The engine doesn't stop unless the car comes to a full stop. When it does a re-start the car must travel a given distance before it will stop again, minimizing stop/start cycles in stop and go traffic. When you come up on a stop sign or red light for a right turn and there's no traffic just do a California stop and it won't shut down at all. If you do want to shut it off it's not exactly a major chore. As for cold engine operation, it doesn't work if the engine, or even the outside temperature, is too cold. After a year with it I don't even think about it anymore.

[Beowulf65]

ASS... I like it, particularly at long stop lights. I've learned to ease to a stop at stop signs and then release the brakes to start forward before the ASS kicks in. This avoids unnecessary engine shut off when I can proceed immediately. With creeping in the city (e.g., when in a long line of cars approaching a stop sign) I have found that after the first ASS cycle the car does not shut off again...programmed that way in my 2016 as noted ^^.

[MomoM3]

Used ASS the first 2 days of ownership and never used it again. Pointless to me. I'd rather not have my car off for any reason other than leaving it.

[usher93]

I hate the feature. I sometimes wonder how much Bmw ended up spending on this in R&d and how much is passed on to us. Such a waste if money in my opinion considering most people have it coded out or simply disable it when in car.

[AudiA4]

I actually don't mind it at all, and don't feel it's overly intrusive...and I drive a manual. The behavior is different with a 6MT...sometimes I can coast forward 20-30 feet without the engine restarting.

[chiefneil]

Originally Posted by usher93

I hate the feature. I sometimes wonder how much Bmw ended up spending on this in R&d and how much is passed on to us. Such a waste if money in my opinion considering most people have it coded out or simply disable it when in car.

It's for their CAFE numbers. I suspect it's one of those things that's more valuable to BMW Corporate than their customers as a whole.

[TheRealEssad]

Rented a 328 for 5 days and used the feature sparingly just to test it out. It aggravated my wife so much I had to turn it off. And she wasn't even driving.

[eluded]

Every time it tries to intervene and shut the motor off... my instinct is to push the clutch in because I think the cars about to stall.

[mbanks21]

Originally Posted by AudiA4

I actually don't mind it at all, and don't feel it's overly intrusive...and I drive a manual. The behavior is different with a 6MT...sometimes I can coast forward 20-30 feet without the engine restarting.

I'm with you with a manual. It's pretty seemless, as soon as I press the clutch and start moving forward the engine starts. I've never had it sputter or delay.