ECO Stop

[wongl]

Wong, there may be times when "a minority of drivers will gain some benefit from this system", you do the majority of your driving in Hong Kong therefore you appear to be one of those drivers. That gain has to be set against the hundreds of thousands of extra starts the engine and components have to endure, we know the system eats batteries and is probably causing the early timing chain failures we are now observing. In my view this is just another layer of electronics that give most drivers little benefit but can cost many hundreds of pounds when trying to diagnose and fix this complex system when it fails to work, which it often does.

Wong said, Quote Many however would like to maintain the ‘4 cylinder’ ECO mode without the actual stopping bit.Quote

It is interesting that you brought this up Wong, cylinder deactivation still works with the Mercedes SLK 55 when the battery sensor is disconnected, it does not work when there is a fault with the sensor, it`s all about doing a little research before making a statement.

Start / Stop / eco tech a load of Bull ...... see #95 comment and read Col`s thread.

I don't know how you came up with the bold statement that "there may be times when a minority of drivers will gain some benefit from this system". Are you suggesting that I am the only driver in the world to gain some benefit from this system? What about the other drivers in HK? How do you know that no drivers in London would benefit from this system? Can you quote/refer to any research or study on this, or is this your own opinion?

The second point regarding Cylinder Deactivation was about providing a choice to owners/drivers of MB cars with ECO Start/Stop. Not everyone wants to deactivate their ECO Start/Stop feature so radically by unplugging the sensor wire at the main battery nor technically enough to fit a by-pass switch. In fact, most drivers in HK would never even open the bonnet/hood for basic routine maintenance like filling up the washer fluid!

 

[wongl]

I used the SLK 200 R171 and the R172 as this car in both iterations used the same 1796 cc engine so can be compared like for like before and after, also the R171 did not have any of the fuel saving technologys fitted to the R172.

Am I the only reader on this forum to observe that it is obvious that if you are not using the ECO Start/Stop feature on the R172, then there is unlikely to be any observable fuel saving on two cars fitted with the same engine?

While I fully understand your concerns regarding the extra wear and tear, especially to the timing chain, I am curious to find out if you have actually conducted any experiments to determine the fuel-saving achievable with ECO Start/Stop enabled vs disabled on your journeys/driving style?

 

[Bobclive2]

6% gain between the two cars not 0.6%, this for all the fuel saving tech, direct injection, turbo,stop/start and regeneration, these are complex computer controlled technologys, is 6% gain worth the high cost of keeping these systems running especially when out of warranty and on the used market.

Direct injection causes severe carbon buildup on the inlet valves causing the engine to run inefficiently which uses more fuel not less.
Turbo`s don`t like being stopped suddenly, especially dozens of times on one journey.
Regeneration means under engine power the battery is never fully charged, this shortens it`s life.
Stop/start, well its all about choices, if the cars on a PCP there are no issues as the car is under warranty and gone in 3 years, when it comes on the used market and this system starts to cause high cost repairs this will lower the used car value and increase leasing costs, here in the UK around 97% of new vehicles are now leased. Remember the Skoda joke, Question (how do you double the value of a Skoda) Answer (Fill it full of petrol). Simple is best, less can go wrong and it`s normally cheaper to fix.

Wong, I was comparing two SLK`s one with the fuel saving technology one without, I presumed the drivers who owned the 2011 to 2016 1.8 Blueefficiency cars were using all the later technology.

Regarding cylinder deactivation, if the stop/start tech was defaulting to off there would be no issues and no surprises at busy junctions if the driver had forgotten to press the stop/start button to off, as it is it defaults to on. Disconnecting the sensor is not just about stop/start it also deactivates smart charging which is causing batteries to be undercharged when the car is driven on mainly short journeys.

London,Hong Kong, New York, doesn`t matter, if the system defaulted to off I believe all would be happy.

 

[markjay]

I don't think that Stop/Start was ever meant to make any meaningful difference at the individual vehicle level.

You have to be very unlucky to spend a significant amount of time during your journey when the car isn't moving at all, and even so the amount of fuel consumed at idle is minuscule anyway. Then, Stop/Start won't be operational all the time due to battery state of charge... and the overall effect of Stop/Start would be very very small indeed.

So I would expect that in the vast majority of cases there would be no noticeable difference in fuel consumption between cars using Stop/Start and those who don't.

Where Stop/Start does make a difference, is in the cumulative effect from thousands of cars in city centres, each one polluting just a little bit less that it otherwise would.

It's a bit like littering - your discarded food wrapper or empty water bottle will make zero difference to the overall cleanliness of our streets; but hundreds or thousands of people doing the same, will.

 

[wongl]

6% gain between the two cars not 0.6%, this for all the fuel saving tech, direct injection, turbo,stop/start and regeneration, these are complex computer controlled technologys, is 6% gain worth the high cost of keeping these systems running especially when out of warranty and on the used market.

Clearly you are not a fan of ECO Start/Stop so presumably you have disabled your ECO Start/Stop via the batter sensor technique or via a Smart-Top device.

You are correct that ECO Start/Stop is a choice, and that's why there is a switch on the console for the driver to disable it when they choose. Clearly you are not a fan, and that is okay as each to their own views and opinion. I hope you have peace of mind that you have done everything possible to preserve your timing chain, injectors, battery, and turbo from premature wear caused by ECO Start/Stop. On the other hand, for me, I think ECO Start/Stop helps to cut the emissions from stationary vehicles in a polluted city and out weights any premature wear and tear.

On my 2011 R172, both batteries were replaced in the 7th year of the car which I think is reasonable given the nature of the congestion and starting/stopping nature of the HK traffic. Apart from the batteries, I have not suffered any premature wear and tear to the timing chain, injectors or turbo in 7 years of hard start/stop traffic. Maybe the extreme summer heat and mild winters ease the potential wear and tear of the constant starting/stopping of the engine? Maybe the lack of high speed driving in HK (the max speed limit is only 120km/h in HK) ease the wear and tear of the timing chain? Who knows?

 

[stu]

Turning it off every time depends on the driver. Some are - shall we say - less mechanically minded. I do not want a call from lane 3 of the M25 saying it stopped and will not restart. Not a good time to day "did you press the button?"

Into the independent tomorrow to check the sensor and swap the battery.

 

[stu]

Yesterday my independent replaced the main battery. Only 4 years old but it had a hard life of short journeys in heavy traffic even before the imposition of the idiotic 20 mpg limit on bug wide roads in West London.

Strangely it seems not to stop and start as much as before, Nothing else was changed.

One question remains. I turned the ECO function off in the setting menu. Made no difference to the ECO stop/start. What does it do?

I have a full command system.

 

[stu]

P.S. The old battery was shoeing 34% so it had no rosy future anyway. I needed a Mercedes battery ( the largest which would fit) as I travel to the continent frequently and need Mercedes recovery cover. I've just had a B service for £404 at a dealer, so all that is far cheaper than the alternative Independent service and AA type cover for each trip.

 

[MarcusRomer]

Hi, new to this so be gentle. I’m looking for Auxiliary battery Mercedes Benz C-class W204 but can’t find anywhere on line I’m in the UK. Any body got a suggestion?

Stop / Stop green Echo light is on dashboard displays ok. When I stop the engine stops, that’s ok but then after 30 seconds or so the engine starts again on its own, the Echo light stay yellow fo several miles before turning green again. I’ve had a new main battery fitted, however, I suspect it’s the Auxiliary battery. the battery is the original from new and the car is a 2012 plate. Any ideas please.

Many Thanks

 

[markjay]

Hi, new to this so be gentle. I’m looking for Auxiliary battery Mercedes Benz C-class W204 but can’t find anywhere on line I’m in the UK. Any body got a suggestion?

Stop / Stop green Echo light is on dashboard displays ok. When I stop the engine stops, that’s ok but then after 30 seconds or so the engine starts again on its own, the Echo light stay yellow fo several miles before turning green again. I’ve had a new main battery fitted, however, I suspect it’s the Auxiliary battery. the battery is the original from new and the car is a 2012 plate. Any ideas please.

Many Thanks

Hmm... doesn't sound abnormal to me. If the ECO light turns green regularly then the Stop/Start is fine. It's an early implementation though so not as clever at the current Stop/Start systems.

 

[markjay]

Hmm... doesn't sound abnormal to me. If the ECO light turns green regularly then the Stop/Start is fine. It's an early implementation though so not as clever at the current Stop/Start systems.

If you must change the auxiliary battery, there are plenty on sale on eBay, just search for 0009827008.

E.g.:

Pardon our interruption...

(This one is made by Exide, which is a reputable manufacturer. Mine was made for MB by Fiamm. But they are all good).

 

[MarcusRomer]

Hmm... doesn't sound abnormal to me. If the ECO light turns green regularly then the Stop/Start is fine. It's an early implementation though so not as clever at the current Stop/Start systems.

It used to work fine then stopped altogether hence the new battery but now it takes a lot longer. May be I should get the auxiliary battery looked at first..

Many Thanks

 

[wongl]

It used to work fine then stopped altogether hence the new battery but now it takes a lot longer. May be I should get the auxiliary battery looked at first..

Many Thanks

Have you tried charging up the new battery overnight? Then try charging the aux battery overnight too. Then retest your ECO start/stop and see if there are any noticeable difference.

 

[MarcusRomer]

Sorry for the delay. No I haven’t as both batteries are fully charged. I have noticed on the auxiliary battery there is a relay attached to the casing. Do you think that the relay is the problem?

Many Thanks

 

[markjay]

Sorry for the delay. No I haven’t as both batteries are fully charged. I have noticed on the auxiliary battery there is a relay attached to the casing. Do you think that the relay is the problem?

Many Thanks

It's difficult to tell. You can try get it connected to STAR and check for any fault codes.

But what I would say, is that if both your batteries show as fully charged and the Stop/Start still isn't working, then chances are that one or both batteries are faulty and need replacing. This does not mean that the main battery won't serve you well for a few more months (or even years), just that it's no longer good enough to support the Start/Stop function.

 

[MarcusRomer]

I find the SS works after 200 yards ie green light displays (weather is hot here so its expected) however when I stop at traffics lights the SS cuts the engine but then restarts it after 15 - 20 seconds without touching any thing. The SS sign stays on yellow for a good 20 minutes before turning green again, and then it cuts of engine when stoped and then starts engine again after 15 - 20 seconds and so on!! Huge mystery

 

[mkhoo]

...weather is hot here...

Is Climate Control on by any chance? SS only stays "off" if there is enough juice in the battery for a correct start up. If there are other demands on the battery when you the engine is Eco Stopped then the engine will restart to mitigate against your battery draining so much it won't restart the engine. This is "normal" behaviour.