Car and Bus Engine Constant Stopping

[feder1]

My car engine persisted in stopping every time the car rolled to a stop until I found the A button that stopped such nonsense.

Today, travelling in a bus, the engine stopped at EVERY bus stop - the bus itself barely stopping to let just one person hop off!

After that the poor engine innards had to be defibrillated back to life, pounding the battery, starter motor, crankshaft, pistons and lots of other things.

DAK what the logic of this peculiar arrangement for modern vehicles is all about please?

[kiloran]

To minimise pollution from the engine idling while at standstill. Particularly effective in congested areas with a lot of stop-start.

--kiloran

[Dod101]

My car engine persisted in stopping every time the car rolled to a stop until I found the A button that stopped such nonsense.

Today, travelling in a bus, the engine stopped at EVERY bus stop - the bus itself barely stopping to let just one person hop off!

After that the poor engine innards had to be defibrillated back to life, pounding the battery, starter motor, crankshaft, pistons and lots of other things.

DAK what the logic of this peculiar arrangement for modern vehicles is all about please?

Why do you call it nonsense? It is green my friend! When I come to a stop not only does the engine stop but it also engages the 'handbrake' if I take my foot off the footbrake, without my doing anything. I think that means that the brake lights do not dazzle the car behind me.

It all works perfectly and marginally helps pollution, and I suppose my petrol consumption. One of the more useful bits about modern car gadgets I would have thought. I have no idea what is required to bring the engine back to life because all I do is press the accelerator and my car takes off smoothly.

Dod

[XFool]

My car engine persisted in stopping every time the car rolled to a stop until I found the A button that stopped such nonsense.

Today, travelling in a bus, the engine stopped at EVERY bus stop - the bus itself barely stopping to let just one person hop off!

After that the poor engine innards had to be defibrillated back to life, pounding the battery, starter motor, crankshaft, pistons and lots of other things.

DAK what the logic of this peculiar arrangement for modern vehicles is all about please?

Isn't this usually characteristic of hybrid drive busses? Where the engine cuts out below a certain speed and drive is handed over to battery drive. Upon pulling away from the stop the main engine drive is reestablished once a set speed is reached.

[Dod101]

I forgot to say that my engine does not cut out on stopping at say traffic lights if I am using the aircon or the heater, presumably so that the chosen cabin temperature can be maintained.

Dod

[monabri]

I've switched the stop-start off (and the "lane guidance" as well as I find it very off putting in daily use and I now switch it off everytime I start the car. I need to read the manual to see if I can permanently disable this function).

[9873210]

The term "pounding the engine" might be better applied to idling, where the engine undergoes several hundred unnecessary explosions per minute. Of course, that only causes minimal damage because the engine is designed* for it. Just as the start/stop engine is designed* to stop and start. There is no undue strain on the equipment.

The old saw was that "much of engine wear occurred when starting the engine". This was true after a fasion but should be restated as "much of engine wear occurs during cold starts". The reason cold start is important is because the oil is goopy, possibly in the crank case leaving bare metal, and moving parts are changing size (thermal expansion) and a bunch of other stuff while the engine is cold. With "cold" added this is still true. But the start stop feature does not do cold starts*. Most will not shutdown the engine until it is warmed up* and nicely lubricated, etc.

Other difference between a stop/start engine and cranking your 1970 Austin Mini are that a modern engine* starts under computer control. The sequencing is much more tightly controlled* so things like flooding the engine just don't happen. Also a stop/start engine should have a larger starter motor* and start at a higher RPM, where it can run comfortably, rather than starting at a bare minimum RPM that causes the engine to lug until it gets up to idle.

* This assumes competent engineering, which is by and large what we have. There will always be a few unfortunate designs, just as there have always been a few traditional engines that melt down in rather fewer miles than the customer would want. There are also tossers who will add a feature so they can claim to have added it without doing the work required.

[quelquod]

When I come to a stop not only does the engine stop but it also engages the 'handbrake' if I take my foot off the footbrake, without my doing anything. I think that means that the brake lights do not dazzle the car behind me.

Dod

Mine (5-series) DOES keep the brake lights on in autohold.

[DrFfybes]

Mine (5-series) DOES keep the brake lights on in autohold.

I really am not keen on this 'innovation'. Brake lights were invented to warn following traffic you were slowing. When stopped you had the option of keeping them on until the car behind has stopped. After that it was usual and polite to release the footbrake so as not to dazzle them at night.

These days you just get a string of LEDs dazzling you at head height.

[PhaseThree]

I've switched the stop-start off (and the "lane guidance" as well as I find it very off putting in daily use and I now switch it off everytime I start the car. I need to read the manual to see if I can permanently disable this function).

The stop-start system reduces fuel consumption, reduces co2 emissions and reduces the pollutants that kill people. If none of this matters to you then go ahead. Poisoning people to avoid something you find "off putting" isn't currently illegal - Morally corrupt but not illegal.

[Dod101]

When I come to a stop not only does the engine stop but it also engages the 'handbrake' if I take my foot off the footbrake, without my doing anything. I think that means that the brake lights do not dazzle the car behind me.

Dod

Mine (5-series) DOES keep the brake lights on in autohold.

I don’t know and I am not sure that I am that bothered!

Dod

[Dod101]

The term "pounding the engine" might be better applied to idling, where the engine undergoes several hundred unnecessary explosions per minute. Of course, that only causes minimal damage because the engine is designed* for it. Just as the start/stop engine is designed* to stop and start. There is no undue strain on the equipment.

The old saw was that "much of engine wear occurred when starting the engine". This was true after a fasion but should be restated as "much of engine wear occurs during cold starts". The reason cold start is important is because the oil is goopy, possibly in the crank case leaving bare metal, and moving parts are changing size (thermal expansion) and a bunch of other stuff while the engine is cold. With "cold" added this is still true. But the start stop feature does not do cold starts*. Most will not shutdown the engine until it is warmed up* and nicely lubricated, etc.

Other difference between a stop/start engine and cranking your 1970 Austin Mini are that a modern engine* starts under computer control. The sequencing is much more tightly controlled* so things like flooding the engine just don't happen. Also a stop/start engine should have a larger starter motor* and start at a higher RPM, where it can run comfortably, rather than starting at a bare minimum RPM that causes the engine to lug until it gets up to idle.

* This assumes competent engineering, which is by and large what we have. There will always be a few unfortunate designs, just as there have always been a few traditional engines that melt down in rather fewer miles than the customer would want. There are also tossers who will add a feature so they can claim to have added it without doing the work required.

Good Heavens. I never thought of all that but can relate to the ‘cold start’ problems that you detail. Much more my era than today’s computer controlled environment. So in fact the op’s worries are more or less without foundation.
Dod

[Alaric]

I forgot to say that my engine does not cut out on stopping at say traffic lights if I am using the aircon or the heater, presumably so that the chosen cabin temperature can be maintained.

It's could be that the engine stays on to continue to supply power to the fan without using the battery. Start/stop requires a chunky battery. I have a Ford Focus nominally with this feature. I don't know if it's the car ageing or the battery, but stop/start rarely works and only when the battery has been charged on a long run.

[monabri]

I've switched the stop-start off (and the "lane guidance" as well as I find it very off putting in daily use and I now switch it off everytime I start the car. I need to read the manual to see if I can permanently disable this function).

The stop-start system reduces fuel consumption, reduces co2 emissions and reduces the pollutants that kill people. If none of this matters to you then go ahead. Poisoning people to avoid something you find "off putting" isn't currently illegal - Morally corrupt but not illegal.

Maybe I should trade it in for a bike? The only benefit of the auto stop-start as far as I can see will be to the manufacturers of batteries and starter motors and to the garages who charge an arm and leg for fitting parts.

I object to being told I'm morally corrupt but not enough to be worried about concerns from eco-warriors!

[chrissyr]

My Peugeot has the same issue. I remember being told that at about 85k miles I might have to replace the battery. Think it is that the battery is more like a leisure one as it need to charge and deplete to low often.
Looking at a replacement it's £100-240 depending on brand.
Still like the stop start option when I'm in traffic for the pollution and mpg benefits.

[PhaseThree]

I've switched the stop-start off (and the "lane guidance" as well as I find it very off putting in daily use and I now switch it off everytime I start the car. I need to read the manual to see if I can permanently disable this function).

The stop-start system reduces fuel consumption, reduces co2 emissions and reduces the pollutants that kill people. If none of this matters to you then go ahead. Poisoning people to avoid something you find "off putting" isn't currently illegal - Morally corrupt but not illegal.

Maybe I should trade it in for a bike? The only benefit of the auto stop-start as far as I can see will be to the manufacturers of batteries and starter motors and to the garages who charge an arm and leg for fitting parts.

I object to being told I'm morally corrupt but not enough to be worried about concerns from eco-warriors!

It really isn't very difficult. Running an internal combustion engine results in poisonous emissions. These emissions kill people. The stop-start systems reduce these emissions. Less emissions means fewer deaths.

https://www.londoncouncils.gov.uk/node/33227
https://www.londoncouncils.gov.uk/downl ... /fid/21944

If you don't like "morally corrupt" find some other suitable elucidation that describes someone who disables a life saving device because they find it "off putting" or are afraid it might cost them a few quid at some point in the future.

(I have had a stop start car in daily use for 9 years - the battery and starter are still fine).

I'm no eco-warrior - but I wont make a conscious choice to poison kids just to save a few quid.
https://www.bbc.co.uk/news/uk-england-london-56801794

[Bouleversee]

Time for a mod. to step in methinks. One can disagree in principle without being offensive.

[quelquod]

I forgot to say that my engine does not cut out on stopping at say traffic lights if I am using the aircon or the heater, presumably so that the chosen cabin temperature can be maintained.

It's could be that the engine stays on to continue to supply power to the fan without using the battery. Start/stop requires a chunky battery. I have a Ford Focus nominally with this feature. I don't know if it's the car ageing or the battery, but stop/start rarely works and only when the battery has been charged on a long run.

From a bit of research mine enables stop/start or not based on a host of parameters - battery charge level, battery health, engine temperature (too cold or too hot), driving mode, towing, aircon to name only the main ones. FWIW I always switch it off anyway as I don’t trust it not to let me down in the middle of the high street, and I simply turn the engine off if there’s a lengthy hold up as I’ve always done.

[Dod101]

I forgot to say that my engine does not cut out on stopping at say traffic lights if I am using the aircon or the heater, presumably so that the chosen cabin temperature can be maintained.

It's could be that the engine stays on to continue to supply power to the fan without using the battery. Start/stop requires a chunky battery. I have a Ford Focus nominally with this feature. I don't know if it's the car ageing or the battery, but stop/start rarely works and only when the battery has been charged on a long run.

From a bit of research mine enables stop/start or not based on a host of parameters - battery charge level, battery health, engine temperature (too cold or too hot), driving mode, towing, aircon to name only the main ones. FWIW I always switch it off anyway as I don’t trust it not to let me down in the middle of the high street, and I simply turn the engine off if there’s a lengthy hold up as I’ve always done.

There are a lot of ‘experts’ around who know what is going on until they don’t. ‘Twas ever
thus.

Dod

[csearle]

I suspect there is a whole field of study to do with nudging people into new behaviour and changing habits, often I presume for reasons associated with the greater good. Time will probably move us in a favourable direction, either because we die-hards are, er, no longer here, or because the reasoned arguments prevail.

Whatever, it is probably fairly difficult for many of us suddenly fully to embrace such changes, so I feel a certain tolerance should be afforded to those that are struggling a bit.

Thanks,
Chris