Stop start module

[Perfectos]

http://bestride.com/research/buyers-guide/does-auto-stopstart-technology-wear-out-engine-components

 

[Legin]

Doesnt address the design of or even the turbo. So how has the turbo been designed for stop start ?

 

[Perfectos]

https://practicalmotoring.com.au/car-advice/myth-busting-stop-start-damage-engine/

 

[Perfectos]

Doesnt address the design of or even the turbo. So how has the turbo been designed for stop start ?

I’m not answering the question I am merely posting some of the available info from the internet.

Both sides have valid argument and counter argument.

In real terms it totally depends on how you use your vehicle, long runs or commutes.

Personally I hate mine, and I turn it off with my most accurate tool I own every time I get in, or if I forget, the first time it kicks in.

I can see why people want to disable it for there own reasons.

People should respect other people’s choices !

 

[Legin]

Still no answer. No point in sending the internet just send the specific. Why are you trying to answer for Welshgas

 

[Legin]

I could easily send arguments that say it does. I spent most of my career in oil and gas working for an oil major btw.

 

[B J G]

I very much doubt if ANY unburnt fuel or poorly combusted gases make it out of the exhaust. A Diesel is not a Petrol Engine. The engine is already hot, so no glowplug required. One cylinder is charged with atomised fuel and air and once compressed by engine turnover it fires. There is in fact very little strain on the starter which is designed for this. Likewise turbos are designed for Stop/Start. In fact reports of early turbo failure are relatively rare.
Totally different when starting from cold as initially the cylinders are heated via the Glowplugs and the cylinder on the compression stroke although charged with air and fuel, that fuel is not atomised and so combustion is unlikely to occur on compression.

My stop/start stops the engine when only 90 yards from the house to the road junction, engine definitely not hot nor anywhere approaching it at that point.
Modern diesels with ultra high pressure direct fuel injection compress the air and the fuel is sprayed in and instantly ignites. This is now a very precise process to enable consumption efficiency and pollution control. There is no premixing with air and subsequent compression.

I'm not aware of an epidemic of turbo failures since stop start was introduced but stopping an engine when it has maximum residual heat is inviting problems.
I recall the high number of cars boiling over on the M5 when they came to a stop at a traffic jam during the holiday season.
Car design has progressed since then but the heat still needs removing and as there is no water or oil flow in a static engine internal temperatures will rise significantly.
T6's have a completely air sealing undertray preventing any thermal air currents cooling the oil sump when stationary.

 

[Perfectos]

Incidentally let’s not go there about pollution, and how selfish others are, when we all drive great big un aerodynamic vehicles, that have used increadible amounts of energy to produce the vehicle during its production and assembly!

Walk or get a bike !

 

[Legin]

Couldnt agree more.

 

[Perfectos]

Still no answer. No point in sending the internet just send the specific. Why are you trying to answer for Welshgas

1) wasn’t aware I was responding on behalf of Welsh gas, I’m sure he’s more than capable of making his own point

2) I’m interested to understand the available information, by available I mean readily available via such resources as the internet.

You’re quick to shoot the OP down but offer very little information, maybe you would like to share some of your wisdom of your years working for an oily, with the other members, so we can all make informed choices btw.

 

[WelshGas]

My stop/start stops the engine when only 90 yards from the house to the road junction, engine definitely not hot nor anywhere approaching it at that point.
Modern diesels with ultra high pressure direct fuel injection compress the air and the fuel is sprayed in and instantly ignites. This is now a very precise process to enable consumption efficiency and pollution control. There is no premixing with air and subsequent compression.

I'm not aware of an epidemic of turbo failures since stop start was introduced but stopping an engine when it has maximum residual heat is inviting problems.
I recall the high number of cars boiling over on the M5 when they came to a stop at a traffic jam during the holiday season.
Car design has progressed since then but the heat still needs removing and as there is no water or oil flow in a static engine internal temperatures will rise significantly.
T6's have a completely air sealing undertray preventing any thermal air currents cooling the oil sump when stationary.

Ok so High Pressure Fuel injected in on Compression, same thing. If no fuel injected then no hydrocarbons in exhaust.
Diesels run much cooler than petrol hence the fact that engine coolant fans rarely on except during regeneration. Also Stop/Start should not function if heat is problematic.

If Stop/Start activates before the Engine has got to Temperature then there is a fault.

For Information.

T6 TPI - start-stop system fails intermittently, engine does not switch off or on -


11/14/2018 Technical product information 2039908/1

Technical product information:
Service info: start-stop system fails intermittently, engine does not switch off or on Transaction No.: 2039908/1
Release date: 27-Feb-2015

Customer statement / workshop findings:

The start-stop system fails intermittently. The engine is not automatically switched off or on.


Technical background:
This TPI only applies to vehicles with the with start-stop system.
The start-stop system allows automatic engine stops and starts.
Because of different factors the engine may not automatically be switched off although the driver expects it.
It is also possible that the engine starts automatically although the driver does not expect it.
For the start-stop system to work there must be no incorrect function and no event entry in the control unit that could affect its operation.


The engine is automatically switched off if the following conditions apply:

• The minimum engine temperature has been reached. Unless this is the case, the system does not switch off
the engine to avoid interrupting the warm-up and to ensure that the heating is available as quickly as
possible.
• The vehicle has exceeded 3 km/h and driven a few metres before coming to a complete standstill.
• On automatic vehicles more than 10 km/h must be reached.
• The charge level of the battery must be sufficient so that the engine can be restarted. To ensure this the
battery manager constantly monitors the charge level of the battery.
• The defrost function of the windscreen is deactivated and the outside temperature is over 3ºC.
• The driver must wear a seat belt.
• A gear must not be selected.
• The clutch must not be pressed.
• The driver door and the bonnet must be closed.
• The engine speed must be below 1,200 rpm.
• The diesel particulate filter (DPF) of the engine must not be in the regeneration process.
• The difference between target and actual interior temperature must not be more than 12ºC.
• The road incline must be under 10º.
• The steering wheel must not be more than 270º (3/4) turned, as the vehicle comes to a standstill.
• On automatic vehicles the brake pedal must be pressed and held as long as the start-stop function is to be
active.
• -
• -
In the following situations the engine is not automatically switched off:
• The vehicle is electrically connected with a trailer.
• The system was manually deactivated with the button on the centre console.
• The clutch is being pressed.
• A gear is selected.
• The brake pedal is not pressed sufficient hard and held.
• The parking aid is switched on.
• The interior temperature selected on the air conditioning system has not yet been reached.
• The charge level of the battery is too low.
• The windscreen is being defrosted.
• The steering wheel is turned more than 270°.
• The vehicle is inclined too much.
• The system remains switched off, if after a replacement the battery has not been adapted with the Guided
Functions or if after such an adaptation the system is in the process of calculating the charging curve. This
process takes about 10 start cycles and varies depending on vehicle and equipment.

In the following situations the engine starts automatically without driver involvement (without pressing the clutch pedal):

• The vehicle moves with switched-off engine and reaches a speed of more than 3 km/h, for example because
of a slope.
• On an automatic vehicle the selector lever position "R" is inserted.
• The coolant temperature drops or rises too much.
• The vacuum in the brake servo has dropped leading to reduced braking assistance.
• The interior temperature differs from value selected in the air conditioning system.
• The outside temperature is below 3ºC.
• The charge level of the battery is below a certain level.
• Many electric electrical consumers are switched on.
• The windscreen is being defrosted.



Requirements for the engine to be started deliberately after being turned off by the start-stop system:

• The clutch pedal must be pressed.
• On automatic vehicles the brake pedal must be released.
• The bonnet must not be open.
• When pressing the clutch pedal the driver door must be closed.
• The seat belt of the driver must be in the belt buckle and must not be released.


Further information about the start-stop system is included in the owner's manual.
Production change

 

[Legin]

Clearly I mistakenly thought you were responding to my post below.

How is the turbo designed for stop start?

Im asking the question as I might learn something as I havent been involved with engine and emissions testing for 8 years.

Based on my 8 years old data nothing has changed in turbo design. Lubricants are much better than they were but that goes back to the synthetics replacing mineral oils way before stop start.

 

[WelshGas]

Clearly I mistakenly thought you were responding to my post below.

How is the turbo designed for stop start?

Im asking the question as I might learn something as I havent been involved with engine and emissions testing for 8 years.

Based on my 8 years old data nothing has changed in turbo design. Lubricants are much better than they were but that goes back to the synthetics replacing mineral oils way before stop start.

Well apart from this mention in one article.
And there’s proof to back this up: Fiat 500 TwinAir owners reported completely failed turbos caused exactly by the stop-start system killing the engine after hard driving. In the case of the Fiat, it’s recommendable to keep the 875cc TwinAir unit running for at least another 30 seconds after you’ve arrived, or more than that if you’ve completed an ascent up a mountain road, or a spritely drive where you did a lot of revving and pushing.
Apart from this one mention I can find nothing related to increased turbo wear in Stop/Start Vehicles.

Non-Stop/Start Vehicles, Yes, lots of articles relating to turbo wear without adequate cooling/idling before engine Stop.

There have been changes in bearings/oils etc: over the past 8 years.

 

[Legin]

Really ? Bearings havent changed in 100 yrs never mind 8 years . Hydrodynamic, pressure fed, roller, dry gas. Metallurgy has advanced and oil tolerance to carbonisation but thats about it.

Your engine still wont run much longer than it ever did without oil so nothing has changed.

A turbo turbine runs at 120 000 plus rpm and takes many minutes to come to a halt, if it comes to a halt more quickly its because of friction which means wear.
Really there is little worse than stopping on a motorway slip road for heat soak, oil drain due to lower viscosity and turbine whizzing. Then switching off the cooling and oil supply.

 

[larrylamb]

There are measures in place to stop diesel turbos from overheating using stop start systems, here are a couple of quotes from Honest John answering peoples concerns.

"Non-stop
I recently asked you about the 1,199cc engine in a Citroen Grand Picasso and was somewhat pleased to see my question appear in last Saturday’s Motoring Section - thank you. I have a follow-up question and wonder if you could offer some more advice, please?
In your email, you mentioned that because of the turbo, I should idle
the engine prior to turning off and this got me thinking about what
would happen if the Stop/Start system kicked in after a long run and
prior to me being able to idle the engine. Is there a safety device to overcome potential problems?

JM, Gloucester

The stop/start will not stop the engine if the turbo is too hot, and in fact that's a good measure, because if you roll into a motorway service station for fuel and the engine does not automatically stop, leave it running for a minute or two because it did not switch off automatically because the turbo was too hot."


"
Pop idle
I have always followed your advice and let the engine of my turbocharged petrol Skoda Yeti ‘idle’ for a few minutes before switching off after a high-speed run. Usually after pulling into a motorway service station for a break on a long fast journey. Everyone is now telling me that there is no need to do that because modern engines have systems that keep the cooling system running if needed. I am still sceptical, so continue to let the car idle for a couple of minutes after a fast run. I am just about to take delivery of a new Yeti 1.2 TSI DSG with stop/start and I wondered if the stop/start system is intelligent enough to know to keep the engine running after a long run. Does it have sensors on the turbo, or will it simply stop the engine as soon as I stop in a motorway carpark? If it stops immediately I am tempted to use the over-ride button and still let the engine idle for a while. Am I being a Luddite, or should I let the engine look after itself?

RT, via email

As a generalisation it depends how "modern" the car is. Many do have pumps that circulate coolant through a petrol turbo after the engine is switched off. Diesel turbos don’t get as hot and usually rely on oil cooling through the turbo bearing only. Stop & start systems use a heat sensor to detect if the turbo is too hot and do not automatically switch the engine off until the turbo has cooled sufficiently. "

 

[Legin]

More likely the coolant thermosyphons which is fine as the quantity is low. However thats just heat management but what about the loss of lubrication ?

 

[WelshGas]

More likely the coolant thermosyphons which is fine as the quantity is low. However thats just heat management but what about the loss of lubrication ?

You forgot Ceramic bearings.
Apparently the new oils have the ability for prolonged lubrication following engine Stop.

I’m only quoting what is available on the Internet.

How about some evidence that Turbos are damaged by Stop/Start? Apart from the Fiat 500 I found a mention of that’s all I found so far and that is only under certain conditions.

 

[flying banana]

I have to feel sorry for a Bloke who posts what he thinks might be helpful information on a small mod to his bus and he gets all this flak. You don't have to do it. It was a tip. Good tip I thought personally. I had similar when I posted about how to remove a key blade to make a surf key without damaging the fob and all I got was a mass argument about vans getting nicked. This forum gets on my tits at times. Well done legin anyway.

 

[Legin]

Ceramic is just a rolling element bearing so didnt forget its in my metallurgy bucket. I wont find direct evidence generally as shorter life like the starters or turbo will be put down to normal wear and tear, its the same failure mode it just happens earlier.
What we do know is starter and bearing wear is increased so life is shorter.
Wont count of course but my friend with a garage sees more starter and battery issues on vehicles with stop start than those without.
Having said that someone says the fiat suffers it so must be an extreme case, how do they know it wouldnt happen anyway ?

 

[Legin]

I have to feel sorry for a Bloke who posts what he thinks might be helpful information on a small mod to his bus and he gets all this flak. You don't have to do it. It was a tip. Good tip I thought personally. I had similar when I posted about how to remove a key blade to make a surf key without damaging the fob and all I got was a mass argument about vans getting nicked. This forum gets on my tits at times. Well done legin anyway.

Thanks for the support. I know what you mean and I half expected it and only posted it in response to a request.

Truth is I find the forum concerning in some respects as some of my posts/threads have been deleted as they have been perceived as threatening to the commercial undercurrent within. Anti competitive some might say.

Dont think I will try again.

 

[WelshGas]

I have to feel sorry for a Bloke who posts what he thinks might be helpful information on a small mod to his bus and he gets all this flak. You don't have to do it. It was a tip. Good tip I thought personally. I had similar when I posted about how to remove a key blade to make a surf key without damaging the fob and all I got was a mass argument about vans getting nicked. This forum gets on my tits at times. Well done legin anyway.

No one is giving the OP grief regarding the installation of a Stop/Start defeat device and his informative post.
However, comments regarding Stop/Start, that it is dangerous/useless/leads to premature failure etc made by some has been questioned and discredited and no evidence presented in support of those comments.

As far as the Forum getting on your ****, then that’s how you see it.

 

[Perfectos]

What post have been deleted ?

That’s concerning, we’re having a debate not a war !

 

[Perfectos]

There is no right and wrong here as no one can give a full and comprehensive explanation to the tech we are told will / does work !

Side issues apart, this is a discussion which I hope will give me a better understanding of the tech on my vehicle and how. Why . What and when it works!

 

[Perfectos]

And importantly if the tech will / can cause damage / has a benefit / has no to little benefit in the real world ?

 

[flying banana]

No one is giving the OP grief regarding the installation of a Stop/Start defeat device and his informative post.
However, comments regarding Stop/Start, that it is dangerous/useless/leads to premature failure etc made by some has been questioned and discredited and no evidence presented in support of those comments.

As far as the Forum getting on your ****, then that’s how you see it.

It read like flak to me. And yes the tits are irked. You would think he had killed a family of polar bears reading some Of it