Start-Stop - Does it save fuel?

[RamFan]

Originally Posted by benjy

how about if you need to move in a hurry where seconds can be a crash or NOT!!

The second you release the brake pedal the engine turns over. If I remember correctly, Mazda's system takes roughly .35 seconds to turnover.

Originally Posted by JohnnyJohnson

Debatable but bet on the fact it will shorten the life of your starter significantly.

This simply isn't true. Starters in these systems are not traditional starters. The only component that MAY experience increased wear and tear is the flywheel but from what I can tell, that isn't confirmed.

 

[BMWTurboDzl]

Originally Posted by wag123

In Texas where it frequently gets well over 100 degrees in the summer, I don't want the engine shutting off at the stop lights. I want the A/C to blow ice cold at all times, especially when I'm sitting at a light. I couldn't give a rat's A$$ about saving a couple of pennys on gas in this situation. My guess is that many of you who live in ares where it gets extremely cold probably feel the same way.

The cars are smart enough to deactivate 'start-stop' when it's extremely hot or cold outside.

 

[BMWTurboDzl]

Originally Posted by JohnnyJohnson

Debatable but bet on the fact it will shorten the life of your starter significantly.

No it won't. The starters were built to be more robust.

 

[demarpaint]

Originally Posted by BMWTurboDzl

Originally Posted by JohnnyJohnson

Debatable but bet on the fact it will shorten the life of your starter significantly.

No it won't. The starters were built to be more robust.

Here's my positive spin on this. Permanently disable stop/start and reap the benefits of the inflated price I paid for a beefed up battery, starter, and charging system, which I had no say in the matter. In the long run my engine will thank me, and the dollar a week I might have saved on gas will go to longer engine, battery and starter life. That for me is a win, win. As always opinions vary.

 

[meep]

It makes a difference in my F150. It's worth at least 0.5mpg on my regular commute which only has a few stops. I'm guessing for my overall it's about 3/4 mpg. I did watch the numbers for a while. It's intelligent enough to NOT shutdown if - engine is cold - batt is low - AC/Heat is on High, esp with defrost on - wheels are not centered - brake pressure is very light - trans is in tow mode IMO they couldn't have done a better job. I don't notice it now.

 

[RamFan]

Originally Posted by BMWTurboDzl

Originally Posted by wag123

In Texas where it frequently gets well over 100 degrees in the summer, I don't want the engine shutting off at the stop lights. I want the A/C to blow ice cold at all times, especially when I'm sitting at a light. I couldn't give a rat's A$$ about saving a couple of pennys on gas in this situation. My guess is that many of you who live in ares where it gets extremely cold probably feel the same way.

The cars are smart enough to deactivate 'start-stop' when it's extremely hot or cold outside.

Yup. For example, on my commute this morning I didn't top 20* so the start/stop never activated.

 

[FlyPenFly]

Originally Posted by Wolf359

Mercedes had it on the 2014+ E-350 models. From the forums, it appears that the starters are fine, but what typically fails is the aux battery that's used for the start stop system. And they're typically failing in under 4 years so factor in the cost of the aux battery. At least it's not as expensive as the main battery. Also I think it's pretty standard that most manufacturers don't let you disable the system permanently, I think only a couple allow you to do it. I had a original starter last over 200k+ in a previous car and they don't seem to fail as often as the past. Alternators still seem to fail on a pretty regular basis though.

The starters are actually much beefier units than you normally find even in Mercedes. The AUX batteries are actually used to keep pressure on hydraulics and the ATF pressure up. The normal battery is used for all start/stop. I've disabled them in my Mercs simply because of the additional strain it puts on mounts.

 

[jeepman3071]

Originally Posted by BMWTurboDzl

Originally Posted by JohnnyJohnson

Debatable but bet on the fact it will shorten the life of your starter significantly.

No it won't. The starters were built to be more robust.

This. I can't really see starters failing earlier or anything like that. My issue with it is a lot of the cars I have driven with it were not very seamless with how it worked and it got annoying.

 

[CKN]

Originally Posted by MNgopher

Lots of talk in here and not a lot of users. I've got it on my 2016 F150 with the 2.7 Ecoboost. Drive a vehicle with start stop if you live in the city/suburbs, and you'll learn quickly how much time you actually spend idling. Hint: Its a lot more than some are willing to admit. The studies I've found are all on the same order as above - less than 10 seconds of idling makes a restart the more economical choice in terms of fuel mileage. I've also figured out very quickly how to make the system do what I want. Don't want it to stop? Don't press the brake pedal so hard and it won't. Easy peasy... Seems like in my typical city driving I can save more than a few tenths of an mpg...

In other words just a normal day on BITOG!

 

[CharBaby]

Originally Posted by RamFan

Originally Posted by Char Baby

I think the jury is still out in regards to the Start-Stop system saving fuel.

According to which jury?

Nothing scientific, just those whom I have spoken to in regards to their specific vehicle with Start/Stop systems. Those who can turn off their own system(not GM) haven't noticed any fuel economy change or it's too close to call from tank to tank. That's all! Could be driving style, climate etc. And some folks I have asked didn't know either way as most people won't anyway. They'll just assume they're getting better fuel economy with the Start/Stop enabled. Another thing about the Start/Stop system that I have heard from these same folks it that, they're not crazy about the way it works for one reason or another.

 

[jeepman3071]

Originally Posted by Char Baby

Originally Posted by RamFan

Originally Posted by Char Baby

I think the jury is still out in regards to the Start-Stop system saving fuel.

According to which jury?

Nothing scientific, just those whom I have spoken to in regards to their specific vehicle with Start/Stop systems. Those who can turn off their own system(not GM) haven't noticed any fuel economy change or it's too close to call from tank to tank. That's all! Could be driving style, climate etc. And some folks I have asked didn't know either way as most people won't anyway. They'll just assume they're getting better fuel economy with the Start/Stop enabled. Another thing about the Start/Stop system that I have heard from these same folks it that, they're not crazy about the way it works for one reason or another.

On my friend's 2015 BMW 335i with stop/start, he noticed a ~1 mpg difference using stop/start. I can get 1 mpg better on my car if I adjusted my driving. For me, the slight hesitation that car has with it enabled was annoying. It was not as bad as a newer Grand Cherokee V6 I drove that had start/stop though.

 

[CKN]

Originally Posted by Char Baby

Originally Posted by RamFan

Originally Posted by Char Baby

I think the jury is still out in regards to the Start-Stop system saving fuel.

According to which jury?

Nothing scientific, just those whom I have spoken to in regards to their specific vehicle with Start/Stop systems. Those who can turn off their own system(not GM) haven't noticed any fuel economy change or it's too close to call from tank to tank. That's all! Could be driving style, climate etc. And some folks I have asked didn't know either way as most people won't anyway. They'll just assume they're getting better fuel economy with the Start/Stop enabled. Another thing about the Start/Stop system that I have heard from these same folks it that, they're not crazy about the way it works for one reason or another.

Under the right circumstances-start/stop does save fuel, just like turning off cylinders, tech that RAM and GM uses. It's not to irritate BITOG Saturday mechanics-it's to meet requirements coming down from the Federal Government.

 

[maxwellk]

Is there an added benefit when you consider the number of vehicles on the road using this technology. The savings for a single vehicle may be minimal but the combined savings of 100,000 vehicles is much more, are the compounded savings enough to have an impact on local fuel demand causing a decrease in fuel price at the pump.

 

[CKN]

Originally Posted by maxwellk

Is there an added benefit when you consider the number of vehicles on the road using this technology. The savings for a single vehicle may be minimal but the combined savings of 100,000 vehicles is much more, are the compounded savings enough to have an impact on local fuel demand causing a decrease in fuel price at the pump.

Exactly. My son's Ford F150 has start/stop-which he likes BTW. AND think of the number of F150s on the road............nationally. This saves fuel-whether it affects fuel prices, who knows.

 

[Kestas]

Originally Posted by maxwellk

Is there an added benefit when you consider the number of vehicles on the road using this technology. The savings for a single vehicle may be minimal but the combined savings of 100,000 vehicles is much more, are the compounded savings enough to have an impact on local fuel demand causing a decrease in fuel price at the pump.

It works both ways... the compounded cost of adding this technology to 100,000 vehicles and repairing it when it goes bad can be tremendous.

 

[CKN]

Originally Posted by Kestas

Originally Posted by maxwellk

Is there an added benefit when you consider the number of vehicles on the road using this technology. The savings for a single vehicle may be minimal but the combined savings of 100,000 vehicles is much more, are the compounded savings enough to have an impact on local fuel demand causing a decrease in fuel price at the pump.

It works both ways... the compounded cost of adding this technology to 100,000 vehicles and repairing it when it goes bad can be tremendous.

Typical BITOG speak. They add new tech-and the first prevalent thought is "What if it breaks?". The issue being is many on here do not understand AT ALL-how the starters for this tech are way different than what are in vehicles now.

 

[RamFan]

Originally Posted by Char Baby

Originally Posted by RamFan

Originally Posted by Char Baby

I think the jury is still out in regards to the Start-Stop system saving fuel.

According to which jury?

Nothing scientific, just those whom I have spoken to in regards to their specific vehicle with Start/Stop systems. Another thing about the Start/Stop system that I have heard from these same folks it that, they're not crazy about the way it works for one reason or another.

Thank you for the response. I was legitimately curious if you had read some finding that point to it being ineffective. With regards to dealing with how it works and not being happy. I get it! Years ago I drove a Saturn Vue with Start/Stop and I will fully admit that the system seemed to be more seamless than the one that's in the Alfa. Not all systems are created equal and some certainly are more noticeable. As this technology is introduced to more vehicles, I'm sure that these complaints will diminish.

Originally Posted by maxwellk

Is there an added benefit when you consider the number of vehicles on the road using this technology. The savings for a single vehicle may be minimal but the combined savings of 100,000 vehicles is much more...

Without question! I think a lot of people are confusing increased fuel efficiency with lower total consumer cost. While I'm not making an argument for or against this latter point, the distinction needs to be made clear. These systems are here to reduce fuel consumption. Period.

 

[gogozy]

I often wonder, the purpose of this is to save resource, and wonder if the starter would fail earlier because of usage, than the one that does not have this technology... what is the cost to manufacturer these starter, do they make pollution during process? what is the final economical/financial/environmental cost to the society? if they have to replace more often, does that make sense to implement this technology? it would mean a waste if gain on CAFE being offset by loss at...EPA? ie, government rebate on CFL and LED light bulbs, CFL bulbs has mercury and all of them are probably manufacture in China or 3rd world country where environmental protection is lacking... while rebate at my hometown reduce cost of ownership and energy usage, these gain may be meanless compare to wasted generate during the process of making these bulbs. I recently spend 3~4 hours on replace starter on my Acura TSX by myself, I can probably get it done about 1.5hr if I wanted; that is still a lot of time (money) think about other activities involved getting it replace, searching parts, buying parts, or schedule a time, drive to a shop etc, if so, it's sounds like the cost of gaining CAFE are transfer to the consumer. here in my city of Toronto most traffic like are not in sync (if they are, then they work to stop traffic); car manufacture, consumer, are being ask and ask, mandate after mandate, urge after urge, to drive and conserve fuel. there is luxury tax, fuel tax, environment tax, carbon tax xxxxxxx.... change to thiner grade oil, ethanol, we consumer had done so much; yet the the group that manage the traffic like act like it has nothing to do with them. can't ask us to do all while themselve does not do any. I have a hard time believe the stop start actually do anything benefit at environment as whole on this planet..

 

[hatt]

Originally Posted by BMWTurboDzl

Originally Posted by Pelican

Originally Posted by demarpaint

It is supposed to save fuel, I'd guess in some instances it does, and some it might not. The question is does it save enough fuel to save the owner of the vehicle money? it's all about CAFE.

It has never been a question of savings for the owner, but everything to do with CAFE

Come on now, over the past 50 years just about every advancement in automotive technology related to the drivetrain has occurred for efficiency and emissions.

Are you saying we'd still be using carbs and points without CAFE.

 

[hatt]

Originally Posted by jeepman3071

Originally Posted by BMWTurboDzl

Originally Posted by JohnnyJohnson

Debatable but bet on the fact it will shorten the life of your starter significantly.

No it won't. The starters were built to be more robust.

This. I can't really see starters failing earlier or anything like that. My issue with it is a lot of the cars I have driven with it were not very seamless with how it worked and it got annoying.

You don't see a system that's used 10x+ more than a similar system failing earlier?