Over-eager start/stop?

[FluffyEyeball]

Well it does have use as it does save fuel, thereby reducing emissions too; saves wear on the engine; reduces the amount of oil used etc. I would't say that's gimmicky. Just in this instance it's been programmed in such a way that a lot of people are not completely happy with.

Also, how's keyless entry and start the same?

[octavianestate]

How much fuel is it saving you?

One could argue that an engine that undergoes constant duty wears less than an engine that is repeatedly switched off and restarted. Thus having to be repeatedly cranked from standstill thus experiencing more mechanical stress. Mechanical parts are subject to MTBF thus I would expect this period to be reduced owing to the above conditions.

The system aids manufacturers in meeting emissions targets right yet at present two manufacturers are 'known' to be have potentially rigged emmission testing. Such technology has not helped in certain cases and once one manufacturer rolls out the tech they all tend follow suit.

The keyless analogy: as above once one manufacturer rolls it out...

[FluffyEyeball]

It's saving more than having the engine running for minutes at a time but not going anywhere. Yes you're right in that manufacturers exploit these systems to increase their sales, and why wouldn't they? The result is still the same, it still achieves the goal intended and reduces the fuel used and emissions expelled. If you were to compare two identical engines with identical use, one with s/s and one without, the one with s/s would use less fuel and emit less emissions.

Yes the manufacturers are lying, but that doesnt impact how effective stop start technology is, and they aren't lying about the stop start figures either. The engines they are lying about would have even higher emissions still without the use of stop start.

How will it cause the engine to wear less? If it isn't moving it isn't wearing, the stop start isn't like the engine doing repeated cold starts.

Same with the keyless entry; yes manufacturers cotton on and copy it and use it as a selling point, but it has various benifits which is why its used in the first place.

[themanwithnoaim]

How much fuel is it saving

I notice the significant fuel saving that Stop/Start has on my car

[octaviaconvert]

Well it does have use as it does save fuel, thereby reducing emissions too; saves wear on the engine; reduces the amount of oil used etc. I would't say that's gimmicky. Just in this instance it's been programmed in such a way that a lot of people are not completely happy with.

Also, how's keyless entry and start the same?

It's not about saving fuel. It's completely about stopping emissions. If an engine isn't running during the relevant part of a test it's not emitting anything. The fact that it's sold as a means to reduce fuel consumption is what makes it gimicky

[FluffyEyeball]

But the two are tied together aren't they. Reduced the fuel you use, you reduce emissions.

There are many ways of reducing emissions, this particular one (amongst many others) is just another way that reduces the fuel used (and thus emissions) without reducing that particular engine size/output.

Edited 28 April, 2016 by FluffyEyeball

[octaviaconvert]

yes and no.  The use of stop/start reduces emissions much more than it does fuel consumption. Anyway, as usual we digress.  This thread was about a start stop system which is unfit for purpose because of the way it just the engine before you come to a standstill which if you drive to a style of progressive braking is dangerous

[octavianestate]

yes and no. The use of stop/start reduces emissions much more than it does fuel consumption. Anyway, as usual we digress. This thread was about a start stop system which is unfit for purpose because of the way it just the engine before you come to a standstill which if you drive to a style of progressive braking is dangerous

I agree that if the engine is effectively not running and you are coasting this is not ideal. You have for a brief moment no full control of the car.

Not sure about driving tests now but years ago 'coasting' was a no no owing to the lack of control scenario.

I'm concious off how much pedal force to apply when braking In the dsg as to avoid engine shut downs. Any junction and roundabout I apply lighter pressure to gradually bring the car to a halt.

If approaching traffic lights that are red I brake to allow the stop start to kick in. I see no discernable savings in fuel consumption.

I see improvements in fuel usage by altering driving style alone.

[cherry evo]

DSG:

 

• light pressure on brake pedal: no S&S
• hard pressure: S&S enabled

   

Very easy to control

 

Yep, already sussed that & I've only had it 4 hours & done about 50 miles!

[octaviaconvert]

I agree that if the engine is effectively not running and you are coasting this is not ideal. You have for a brief moment no full control of the car.

Not sure about driving tests now but years ago 'coasting' was a no no owing to the lack of control scenario.

I'm concious off how much pedal force to apply when braking In the dsg as to avoid engine shut downs. Any junction and roundabout I apply lighter pressure to gradually bring the car to a halt.

If approaching traffic lights that are red I brake to allow the stop start to kick in. I see no discernable savings in fuel consumption.

I see improvements in fuel usage by altering driving style alone.

I'm just going to disable mine through VCDS, I feel it's safer all round

[Gabbo]

I think most people miss the point of what StopStart is intended to do.

It was introduced to reduce CO2 emissions on the European emissions cycle.

 

It has the added benefit of reducing localised polution for e.g. in city with heavy stop start traffic but no manufacturer would add a system just for this unless there was a financial incentive behind it.

 

Unless your car sits at idle for hours every day, stopping the engine for 20s at a traffic light isn't going to save you more than a few drops of fuel each time & remember you have to offset the fuel saved when the engine is stopped against the fuel required to restart the engine.

 

What it does mean is that the manufacturers can achieve 99/109/119g/km to keep their car attractive from a sales perspective.

 

 

For me, if it is fuel neutral but helps to improve the air quality Inside towns, cities & where I live its a good thing.

You just need to be realistic about what you expect it to achieve.

[alancha]

Like many others, it seems, I turn SS off as soon as I've started the engine or, if I forget to do it then, the first time it kicks-in on the road. 

 

To be fair, most of the time it works OK (manual vrs tdi) but there are occasions when you're stopping at a red light, for example, which then starts turning to green just as the car decides to turn the engine off.  Unfortunately, in that situation it insists on completing the "off" process before restarting the engine, causing a small but annoying delay (annoying to me and probably the car behind me).  I also don't like the rattly sound of the diesel engine restarting every time.  

[ednmra]

Still hate it! I want the engine on when I want it on, and off when I turn it off. On the odd occasion I forget to disable SS on start up, and it does its stuff, I realise once again how much I dislike it.

 

If I'm in a minority of one................I still hate it !!!

[Item]

Spoke with the dealer whilst they looked at an unrelated issue to see if there was any calibration/adjustment that could be done...and apparently not - this is just the way it behaves!