Tried to searching for this so apologies if already covered.
When you're in ASS mode, what is the minimum time you allow for the car to stop? I drive in the city often and at stop lights I can see the pedestrian crosswalk countdown, so if I see less than 15 seconds left I'll shift to manual/sport mode to keep the engine running.
Does anyone have guidelines on how long before it doesn't make sense to let engine stop?
Why shift to sport and burn more gas, just turn of ASS before you come to a stop instead of changing engine modes. If you like ASS, saving gas and the environment, just leave it on, SF traffic is bad enough that you will save gas on average.
BMW's manual says ASS may cause wear on some components - assume whatever components are used for starting up the engine. If you read "green" websites, they say you burn 10 -15 seconds worth of gas needed to idle for engine startup. Between this wear and the balance where you can actually "save more gas than you require to startup + enough gas to offset costs for your wear", I would say your car needs to idle at least 30 seconds on average.
If you read "green" websites, they say you burn 10 -15 seconds worth of gas needed to idle for engine startup. Between this wear and the balance where you can actually "save more gas than you require to startup + enough gas to offset costs for your wear", I would say your car needs to idle at least 30 seconds on average.
I've read somewhere but can't find it, that you begin saving fuel after 3 seconds stopped. The closest thing I can find comes from our owner's manual:
F30 Owner's Manual said:
Auto Start/Stop function
The Auto Start/Stop function of your vehicle automatically
switches off the engine during a
stop.
If the engine is switched off and then restarted
rather than leaving the engine running constantly,
fuel consumption and emissions are reduced. Savings can begin within a few seconds
of switching off the engine.
I am torn on ASS ( that doesn't sound comfortable). It seems to be fine and worthwhile if there are tons of stoplights, but is a major drag in stop and go traffic or on neighborhood streets with stop sign after stop sign, like we have here. The problem is that most places I go have an inconvenient mix. I also find it promotes what I have always referred to as the "California rolling stop" (no offense) which could be dangerous and makes me the ass avoiding ASS by not stopping when I should. Now head hurts, or is that my a**?
There's an advocacy group that gives away bumper stickers. They claim that ten seconds is the threshold.I fear they are to bent on saving gas, not repair bills. Therefore, my cutoff is 20 seconds.
I turn off ASS except n a few stretches of road. I save about 15 min. per week, which might save 1/4 gallons a week.
For several reason...including the fact that about 90% of my driving is on Interstates...my ASS is always off.In fact,it would be off even if 100% of my driving was Manhattan rush hour traffic.Too much annoyance...too much bother.Things haven't gotten so bad for me just yet that I need to save a couple of dollars a week by engaging this feature.And as for "pollution"...couldn't care less.
I found ASS most useful in suburban driving where the traffic lights can be a minute. Downtown traffic often has frequent stops but of too short duration.
Mine is off during summer when a/c is on most of the time. On most lights ASS comes on before light turns green to run a/c and for some reason it's much rougher start than when I take my foot off brake pedal.
+1. Bought my car in December and tolerated the ASS until it got hot outside. Now it's turned off. I may switch back in October because I do like the quiet while sitting at lights.
We do too. I agree it works well. It's pretty seamless, I see no reason not to use it. I suspect maybe on earlier model years it was rougher starting/stopping?
We've actually timed our red lights. Many of them last as long as five minutes. We use the ASS feature around town and feel that we've saved a few bucks. I like my cars, but I'm also a penny pincher once they're in the stable. I'll wring the car out on a fun windy road, but in the city I use ASS and Eco mode.
It's seamless when I take my foot off brake. When it decides to start it while my foot is on brake, it's much rougher. I saw this on test drives and on a loaner, so it's not just my car (2014 328i)
Also I should mention that my problem with ASS is that I live in Texas. 100 degree weather. ASS only lasts about 15 seconds with the AC on. It's practically useless where I live, and I hate being surprised when the car comes back to life on its own.
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
BimmerFest BMW Forum
11.4M posts
753.1K members
Since 2001
A forum community dedicated to BMW owners and enthusiasts. Come join the discussion about Bimmerfest events, production numbers, programming, performance, modifications, classifieds, troubleshooting, maintenance, and more! Bringing the BMW community together.