Hi, I'm not mechanic so if stupid question, please let me know that. 

 

I have got last years Octavia 1.6 TDI engine with DSG and of course start-stop system is always on, only if I switch it off manually. 

As perhaps, many people, I have few concerns about life expectancy of some parts of vehicle if started something 20 or more times per day. 

 

Maybe any comments on that? 

First of all concerns are about batteries life and starter systems life. Perhaps there are even more systems having greater load because of that.

 

Another question is about real impact on efficiency and ecology, is there any improvement at all? Perhaps there is, as otherwise manufacturer wouldn't implement such tech.

 

And one more, if I think start-stop is best of the best options, isn't there any way to make it stop engine even if comfort temperature is not reached yet. As in moderate weather there is no issues to wait few minutes longer to get heat inside. I have played with AC system, there are a lot of times when car immediately stops engine after I turn off comfort system. In really cold weather there will be engine or other parts temperature limitations so it will run anyway.

 

And fianlly, when I look at messages why start-stop system is not active yet, there are several reasons, like engine temperature not reached, or comfort temp not reached. Perhaps, most funny one, at least for me, is, I don't know exactly how it is in English as I have localized version, but it can be translated as - Engine must run. 
Of course it is quite important excuse, but anyway dose anyone have a clue  what can that mean?

 

Thanks! Cheers!

 

Manufacturers implemented what they needed to to meet the Emission Results in EU testing as Governments introduced, or as VW did they cheated and introduced stuff as well.

 

The engines when stopped are not emitting emissions so that bit works, and there are plenty years gone by with Stop / Start vehicles showing the components stand up to use.

As to some cars batteries, some manufacturers fit cheap rubbish not really fit for purpose.

My Dec 2014 Octavia seems to be on it's original battery and since I took ownership of it last March, I've used stop/start quite a bit (will use a little common sense rather than letting it cut in every time I come to a standstill.

I go through 9+ sets of traffic lights on my 16 mile to work (and then on the way home).  Depending on the traffic and road conditions you can spend quite a while sitting there going nowhere so it can make a difference not having the engine running.

 

I know some people are dead set against stop/start due to perceived stress & strain on the ignition system but as Skoffski says, there are plenty of older cars that have start/stop that aren't exhibiting these perceived issues.

Yeah as others have said, the components are designed to deal with the extra number of start cycles, so you don’t need to worry  

 

Sitting in traffic, do you really need the engine running? Probably not. I certainly don’t. If more power is required, or the temp isn’t right then it will restart itself.  

Being  a driver and pedestrian (and occasional cyclist) I appreciate not being poisoned as much by vehicles spitting out clouds of rubbish when they are not moving  

Best to let the car denote what is best.  If the battery voltage is low, the car won't go into stop/start mode anyhow.  A good long run should fix that.

1 hour ago, Gumby said:

Yeah as others have said, the components are designed to deal with the extra number of start cycles, so you don’t need to worry  

 

Sitting in traffic, do you really need the engine running? Probably not. I certainly don’t. If more power is required, or the temp isn’t right then it will restart itself.  

Being  a driver and pedestrian (and occasional cyclist) I appreciate not being poisoned as much by vehicles spitting out clouds of rubbish when they are not moving  

I need my engine running. I'm cold blooded and only take my coat off when it gets to 30'. The heater on my diesel is like warming your hands on a candle from the other side of a field. And the candle isn't even lit.

I'll turn it on in summer, honest

1 hour ago, Gumby said:

Yeah as others have said, the components are designed to deal with the extra number of start cycles, so you don’t need to worry  

 

Sitting in traffic, do you really need the engine running? Probably not. I certainly don’t. If more power is required, or the temp isn’t right then it will restart itself.  

Being  a driver and pedestrian (and occasional cyclist) I appreciate not being poisoned as much by vehicles spitting out clouds of rubbish when they are not moving  

 

100% agree with all of this. 

In terms of stress on the battery & starter, these components are obviously updated/validated for stop/start systems.

But even without stop start, think if your driving profile is even close to the worst case?

Before stop/start there were taxis running 24hrs a day, delivery vans, post office cars which would stop & start hundreds of times a day, everyday, every month, every year...

 

 

None of the manufacturers really wanted StopStart but it was an easy way to drop an emissions class because during the the European Test Cycle (before WLTC was introduced) there was a long "idle" period to simulate waiting at traffic lights & in traffic.

Hence, now we have it...

In real terms the fuel saving is negligable but perhaps its better to think about the air quality in cities or busy areas... 

43 minutes ago, Gabbo said:

In real terms the fuel saving is negligable but perhaps its better to think about the air quality in cities or busy areas... 

I agree. According to the computer in my Nissan I’ve saved about 20kg of CO2 (however reliable that is!) which very roughly equates to 125 miles of driving (based on ~100g/km). Of course that’s not entirely the same as fuel economy either, but over almost 19k miles it’s clearly made very little fuel savings. 

 

However if I really have saved 20 kg of CO2, although that sounds insignificant, there are over 38 million cars in the U.K. which is 3/4 billion kg, 750,000 tonnes less CO2 in the atmosphere. Ok, all very rough and probably still a drop in the ocean, but better than nothing. 

I have disabled start stop on vcds by increasing the voltage threshold.

 

I did it not for concerns on starter motor stress. I was more concerned with engine mounts wearing prematurely as you will see engines wobble when starting and stopping, and more abruptly than when revving. This may not manifest itself as a failure, just general feel of older car quicker and notchier gear change. You can feel a woobly engine in the cabin when you accelerate. 

 

Secondly, oil circulation. The engine components should be covered with oil when its been running and a temporary stop should be ok. But if your oil is at the end of its life have a look at its viscosity. The oil is not always as good as when you first put it in your car and end of life oil plus stop start I believe add unnecessary strain. Secondly parts which run in an oil film (such as some bearings). When these parts are moving they are actually disconnected from each other as there is an oil film. As soon as you stop an engine any parts which are under force will make contact again and push the oil film out. Again this won’t manifest itself in a failure but a premature wear possibly leading to reduced power (its compression is lost). 

 

If you’re running dpf, dpf regen requires getting to temperature for a regenration to occurr (if its dry dpf and not add blue). If you stuck in traffic and your engone is off reducing the exhaust temp. Once you set off and start travelling above 40mph between 1800rpm to 2500rpm, if your car was ready for a regen under normal circumstances, it would then have to wait to reach to temp (around 550 if i’m correct). It may sound trivial but I’ve watched on vcds how longs it takes a diesel engine to warm up the exhaust. 

 

On older cars with start stop I wouldn’t expect to see the above issues being identified and then people immediately saying “oh its the start stop”. They are general wear issues just happening quicker. 

52 minutes ago, briskoda1 said:

 

 

If you’re running dpf, dpf regen requires getting to temperature for a regenration to occurr (if its dry dpf and not add blue). If you stuck in traffic and your engone is off reducing the exhaust temp. Once you set off and start travelling above 40mph between 1800rpm to 2500rpm, if your car was ready for a regen under normal circumstances, it would then have to wait to reach to temp (around 550 if i’m correct). It may sound trivial but I’ve watched on vcds how longs it takes a diesel engine to warm up the exhaust. 

 

 

 

Stop/Start doesn't work if a regen is imminent or in progress.

I saw on the VAG DPF app that one was scheduled so I drove a little more enthusiastically when I left work, before the coolant temp had even lifted the needle (about 5 mins into the journey, it had gone into regen mode, holding the revs at 1K at idle and wouldn't allow stop/start until the process was complete

 

1 hour ago, Russ77 said:

 

Stop/Start doesn't work if a regen is imminent or in progress.

I saw on the VAG DPF app that one was scheduled so I drove a little more enthusiastically when I left work, before the coolant temp had even lifted the needle (about 5 mins into the journey, it had gone into regen mode, holding the revs at 1K at idle and wouldn't allow stop/start until the process was complete

 

How do you know if you car has gone into regen mode? Is there a warning light on the dash telling you? I've done a few hundred miles since getting mine and never noticed anything yet...

10 hours ago, NikTheGeek said:

How do you know if you car has gone into regen mode? Is there a warning light on the dash telling you? I've done a few hundred miles since getting mine and never noticed anything yet...

 

I can normally tell when the revs start holding at 1K when Idling but I invested in a bluetooth dongle from Amazon and the VAG DPF app which shows you what's going on with your DPF i.e. when it's going through a regen, how long since the last regen and probably more importantly, how much oil ash residue it has as this will ultimate determine when your DPF is at the end of it's serviceable life (which from general consensus on here seems to be 150K-170K depending on useage & driving pattern).

 

Mine seems to regen every 300 or so miles.

 

 

I like the stop start system, my 2016 Scout is the first car Iv owned with this system and it only felt strange for the first time I drove it, dont worry about the starter and battery they are beefed up to cope with the extra work involved.

17 hours ago, briskoda1 said:

I have disabled start stop on vcds by increasing the voltage threshold.

 

I did it not for concerns on starter motor stress. I was more concerned with engine mounts wearing prematurely as you will see engines wobble when starting and stopping, and more abruptly than when revving. This may not manifest itself as a failure, just general feel of older car quicker and notchier gear change. You can feel a woobly engine in the cabin when you accelerate. 

 

Secondly, oil circulation. The engine components should be covered with oil when its been running and a temporary stop should be ok. But if your oil is at the end of its life have a look at its viscosity. The oil is not always as good as when you first put it in your car and end of life oil plus stop start I believe add unnecessary strain. Secondly parts which run in an oil film (such as some bearings). When these parts are moving they are actually disconnected from each other as there is an oil film. As soon as you stop an engine any parts which are under force will make contact again and push the oil film out. Again this won’t manifest itself in a failure but a premature wear possibly leading to reduced power (its compression is lost). 

 

If you’re running dpf, dpf regen requires getting to temperature for a regenration to occurr (if its dry dpf and not add blue). If you stuck in traffic and your engone is off reducing the exhaust temp. Once you set off and start travelling above 40mph between 1800rpm to 2500rpm, if your car was ready for a regen under normal circumstances, it would then have to wait to reach to temp (around 550 if i’m correct). It may sound trivial but I’ve watched on vcds how longs it takes a diesel engine to warm up the exhaust. 

 

On older cars with start stop I wouldn’t expect to see the above issues being identified and then people immediately saying “oh its the start stop”. They are general wear issues just happening quicker. 

 

So you’ve got your reasons for doing this, which I respect, but disagree with. 

Your concerns about oil and engine mounts I think are unfounded.  These are modern cars, which are designed with all other components in mind. The start stop system isn’t just a bolt on afterthought. It’s addtion will have been carefully thought out and it’s potential impact on other parts.  The system will stop the crank shaft etc in such a position so it’s as easy as possible to restart when needed, whilst causing the least amount of stress on the engine.  The amount of time the engine is stopped for won’t be enough for the oil to flow out or away to such a degree that it causes contact between parts.  If you have evidence it does, then I’m sure VW/Skoda would love to hear it. 

As for engine mounts, again, they will have thought of that. Either stronger mounts, or they’ve determined there is little impact on them when start stop is active. 

 

As I said above, you’ve got you reasons. It’s your car and you can do what you like with it.  This is just indented to be constructive criticism of your points, and I’d encourage you to think again about disabling start stop. I’m sure you’d appreciate less toxic air too  

How many SS enthusiasts really believe that there won't be a negative impact on battery lifetime?

 

Recycling dead lead-acid batteries is going to have an environmental cost. See Parting Shot paragraph here: https://www.ecomena.org/managing-lead-acid-batteries/

 

" It is to be noted that recycling of used lead acid batteries is not a simple process that can be undertaken in small scale enterprises. Infact lead-acid battery recycling is regarded as one of the worst polluting industries worldwide"

 

 

I wouldn't be at all surprised to learn that stop-start was halving the average battery lifetime, but don't have stats about this.

Edited 15 January, 20197 yr by Wino

Some VW Group battery lives / longevity are pathetic even without Stop / Start fitted, functioning or enabled. 

Some batteries and stop start systems in a Mk3 Fabia are not fit for purpose, like driving all year round in City / Small cars or medium cars in Villages, Towns, Cities where there are lots of traffic stopped and engines might be expected to be off, petrol or diesel.

 

Battery Regen on some models just useless.

 

 

Given that VW Group have never sourced quality water pumps since they went from air cooled engine maybe best if people think of 'Running Time' and not miles as with 

Generators, Planes, Boats, Heavy Plant etc.

 

Crap water pumps that might be best just running on a while after engines are switched off like oil pumps.

 

Looking forward to seeing how VW Group get on with Cooling EV batteries once they eventually manage to actually have cars on offer with any decent Capacity in batteries and Fast Charging.

VW always on about 48volts and combined water / coolant pumps and starter motors and Electric Superchargers and as usual it shows a bit with Audi, 

but then as usual with 'Vorsprung Durch Technik'  it is someone else's technology and they are too tight to actually buy into the licence and pay the owners of a patent.

Edited 15 January, 20197 yr by Skoffski

48 minutes ago, Gumby said:

 

This is just indented to be constructive criticism of your points, and I’d encourage you to think again about disabling start stop. I’m sure you’d appreciate less toxic air too  

 

No worries, its just healthy debate. 

 

My car is petrol which has a cat. Petrol cars which are running to temperature should just emit co2 and water. Neither of which are toxic. Co2 is a man-made greenhouse gas.

 

if I wanted to actively reduce my carbon footprint I would probably not drive a 2 litre petrol, or no longer buy any VAG group car, or walk. There are more effective ways than prematurely wearing an engine. 

 

If I was really worried about toxic fumes (i presume you mean NOx, CO and PM I would no longer be driving diesels. Which I don’t.

 

I’m an degree qualified mechanical engineer so the comments on oil are basic properties of oil adhesion on metal surfaces and the film that it creates under movement, shouldn’t be unfounded you’ll find it in any good text book. You could do it as a fun experiment at home if you like.

 

Engine mounts are a wear item, but not necessarily a replacement item. They wear as a result of them having to absorb forces (nothing unfounded here?). The more repeated force the quicker they wear. Again this should be easy to understand and not controversial. What you’d classify as being a good mount is then subjective. If i were offered a mount from a 10 year old car that had a life of start stop vs a car that had it switched off, I know what I would choose.

 

Each to their own though, as you say.

 

 

 

^^^ Reading that one might wonder why now VW Group Petrol Engine cars have a Gasoline Particulate Filter.

  Just something that was not necessary......

 

VW are maybe looking for good engineers that can help them with the 1.5 TSI's pre and post WLTP that have kangerooing issues.

They might want to be careful to which countries they travel too and take soap on a rope with them incase they might end up in 'Shared Accommodation'. for a year or 3. 

Edited 15 January, 20197 yr by Skoffski

2 hours ago, Wino said:

I wouldn't be at all surprised to learn that stop-start was halving the average battery lifetime, but don't have stats about this.

 

I have noticed that aftermarket batteries for a stop start Octy are around £300 and only have a 3 year guarantee. Go figure. 

2 hours ago, Wino said:

How many SS enthusiasts really believe that there won't be a negative impact on battery lifetime?

 

Recycling dead lead-acid batteries is going to have an environmental cost. See Parting Shot paragraph here: https://www.ecomena.org/managing-lead-acid-batteries/

 

" It is to be noted that recycling of used lead acid batteries is not a simple process that can be undertaken in small scale enterprises. Infact lead-acid battery recycling is regarded as one of the worst polluting industries worldwide"

 

 

I wouldn't be at all surprised to learn that stop-start was halving the average battery lifetime, but don't have stats about this.

Car batteries are 99% recycleable. The battery industry in well developed regions reclaim as many batteries as possible to extract the lead for new batteries. Hence a base core value for batteries and recycled lead in general. Its cheaper and easier to recycle rather than hauling it out of the ground. That article seems to focus on attitudes in less developed regions. Developed countries are heavily regulated for movement and disposal of batteries under UN directives.

 

https://www.johnsoncontrols.com/batteries/battery-recycling

 

As for battery lifetime. unless the battery has been damaged from a discharge related event, they will be perfectly capable of lasting 10 years in the vehicle it was first fitted to. Batteries need replacing if they have been damaged from discharging which is really easy to do if not taken care of from the moment they are connected up in the factory. EFB and AGM batteries are used specifically for Stop/start applications as they are way more durable than a standard flooded battery.

 

The biggest killer of batteries is long idle stand times of 30 days or more or regular short journeys/plugged in accessories depleting the voltage with not enough engine run time to recharge it fully. The other end of the scale is the taxi duty cycle which wears batteries out way quicker than the average through the hammering they get with constant vehicle use.

8 minutes ago, BigEjit said:

As for battery lifetime. unless the battery has been damaged from a discharge related event, they will be perfectly capable of lasting 10 years in the vehicle it was first fitted to

Riiight.

2 minutes ago, Wino said:

Riiight.

I have the stats!!

Please share.

Wish I could... But I need to keep my job!