[E90Fleet]

Originally Posted by Q4P

Was the first generation of this system installed on DI turbo gas motors with HPFPs? The more complexity, the more issues... it's basically common knowledge. Users experiences are confirming this.

I experienced starter issues on my N54 without this system... I can't imagine this being a better setup. I will take reliability over fuel efficiency any day. The 8 speed tranny and small displacement turbo motors are enough to pass emissions.

1) My post was in response to a question on starters specifically, not the engine as a whole. Talking about HPFP's, the F30 has a completely different one than the E90 models.

2)Tell regulators about the emissions, they are requiring the stop/start systems in upcoming regulations. Manufacturers are just having to follow. Even tougher regulations are in the near future.

[Q4P]

Originally Posted by E90Fleet

1) My post was in response to a question on starters specifically, not the engine as a whole. Talking about HPFP's, the F30 has a completely different one than the E90 models.

2)Tell regulators about the emissions, they are requiring the stop/start systems in upcoming regulations. Manufacturers are just having to follow. Even tougher regulations are in the near future.

I understand... I am merely referring to complexity. A starter that restarts itself every 5 seconds in city traffic just sounds like a reliability nightmare.

[JoeyO]

I don't have an issue withe the technology. I have an issue with the half-ass approach BMW has taken. It seems like they have some serious bugs to work out. The start/stop system has been known to stall out on several people on this forum and with Motor Trend editors. This is what the Motor Trend editors wrote:

The biggest problem we discovered came from the automatic stop/start system. On three occasions, the system deactivated itself while the car was stopped at a light with the engine off, leaving its driver stuck in neutral with a line of honking, angry drivers rapidly forming behind.

Geeze, 3 times it happened? That doesn't sound like a fluke. That sounds like bad engineering. So much for 4 years of experience in Europe. Big deal, if the technology is still not implemented correctly 4 years later.

By the way, I believe the original poster is oversimplifying the conversation. But as an engineer myself I totally get his point. You guys are kidding yourselves if you don't think engineers are under extreme pressure to release products that they're not entirely 100% confident with and "just need a little more time to work out." That's life and it happens all the time.

[Feanor]

Originally Posted by Q4P

I think the main issue with this will be reliability... I can almost guarantee starters will go out much sooner than they should.

Care to elaborate, bearing in mind my earlier post?

Originally Posted by Feanor

From what I understand the only thing that's likely to wear out from heavy use in a starter is the relay, and I have heard that manufacturers of cars with stop-start technology get around this by somehow avoiding the use of relays.

Unless someone understands the technicalities then I think it's completely bonkers to just assume stop-start will wear out the starter. I agree it's a concern, but as I said, the reliability & potential repair costs of adaptive suspension is far more of a concern to me and I don't see that causing anywhere near as much controversy.

Originally Posted by Q4P

I understand... I am merely referring to complexity. A starter that restarts itself every 5 seconds in city traffic just sounds like a reliability nightmare.

I know you're mostly being facetious there but it doesn't restart itself every 5 seconds. I actually get a bit annoyed with my 118D because in traffic it often DOESN'T turn itself off for various reasons, and I hate sitting there burning fuel for no reason. I actually wish there was an option to manually trigger the stop/start function so that the car would be ready to go when I press the clutch.

So many parameters have to be right for the engine to turn itself off at all in the first place. Engine temperature; ambient temperature between +3 C and (I think) +27 C; battery levels; cabin temperature; whether the start/stop has already activated a few times in the last few minutes.

This all means that in practice, start/stop really isn't turning the engine on and off all the time.

Now if people were just complaining about the problems we've been hearing with the start/stop function then that'd be fair enough - we shouldn't accept problems of any sort with a car like this. As JoeyO said, there does seem to be a problem with some cars and that's not right when the technology has been around for years.

What's annoying me a bit is that so many people are making crud up and stating it as fact to justify why they don't like the technology.

[328inGE]

Originally Posted by JoeyO

This is what the Motor Trend editors wrote:

The biggest problem we discovered came from the automatic stop/start system. On three occasions, the system deactivated itself while the car was stopped at a light with the engine off, leaving its driver stuck in neutral with a line of honking, angry drivers rapidly forming behind.
.

I wonder how much of this is due to operator error?

[328inGE]

Originally Posted by Q4P

I will take reliability over fuel efficiency any day. The 8 speed tranny and small displacement turbo motors are enough to pass emissions.

You understand this technology is not just for the benefit of the driver, right?

[Mahzari]

I prefer having Start-Stop technology than the alternative (smaller engine, less horsepower). Especially because you can turn it off. Stop complaining, BMW has to meet CO2 and MPG regulations, and they elected to have Start-Stop technology so they didn't have to downsize the engine, put a 9 speed transmission, or do anything else stupid etc. etc.