Clubjazz - Honda Jazz & HR-V Forums

Honda Jazz Forums => Honda Jazz Mk3 2015 - 2020 => Topic started by: Skyrider on April 13, 2017, 06:55:42 PM

Title: Idle stop, on or off?
Post by: Skyrider on April 13, 2017, 06:55:42 PM
I have been turning my idle stop off for a couple of weeks, it has made no difference to my fuel consumption other than it has improved slightly (warmer weather?). I believe the idle stop is designed to assist Honda with statuary testing results rather than do the owner any good. I now only turn on the idle stop if I am in heavy traffic where the car will be stopped  for more than 2 minutes. This makes normal driving with short stops far more pleasant and is a lot easier on the car.
Title: Re: Idle stop, on or off?
Post by: Paulwhitt20 on April 14, 2017, 10:31:54 AM
I think idle stop works best when used in conjunction with a hybrid engine. Then it can just do its thing. Such a pity that after pioneering the hybrid car and having three hybrid cars in their range, Honda dropped hybrid technology in favour of the 1.6 Diesel engine and diesels are now doomed.
Title: Re: Idle stop, on or off?
Post by: peteo48 on April 14, 2017, 12:24:11 PM
I have been turning my idle stop off for a couple of weeks, it has made no difference to my fuel consumption other than it has improved slightly (warmer weather?). I believe the idle stop is designed to assist Honda with statuary testing results rather than do the owner any good. I now only turn on the idle stop if I am in heavy traffic where the car will be stopped  for more than 2 minutes. This makes normal driving with short stops far more pleasant and is a lot easier on the car.

https://www.youtube.com/watch?v=k159M8QhCIE (https://www.youtube.com/watch?v=k159M8QhCIE)

I just love this guy. He agrees with you.
Title: Re: Idle stop, on or off?
Post by: culzean on April 14, 2017, 01:44:47 PM
stop - start is another example of fuel consumption tests being skewed by test regimes that are favourable to laboratory testing but have very little basis in real life driving. I have been passenger in stop-start cars and I reckon I would be switching it off as well if I was driving.
Title: Re: Idle stop, on or off?
Post by: peteo48 on April 14, 2017, 03:11:50 PM
I do my own manual version of stop start at certain lights where I know what the sequence is and how long I'm going to wait and, of course, I don't idle unnecessarily but these systems detract from driving comfort and pleasure and at a negligible fuel saving.
Title: Re: Idle stop, on or off?
Post by: Downsizer on April 14, 2017, 03:26:12 PM
Gentle brake pedal pressure is often enough to stop the car without stopping the engine for short stops.
Title: Re: Idle stop, on or off?
Post by: guest6570 on April 16, 2017, 12:03:34 PM
Whatever the arguments are for reducing fuel consumption it is not the only reason for the system to be there, it is there to also reduce emissions and therefore benefits the driver by lowering their tax liability. Stop/Start if used by all those drivers who have it would also benefit the environment. Thousands of cars or even millions worldwide all stopped at lights burning fuel is no good to anyone whether its for a few seconds or fractions of a minute - use stop start and save the environment! I've had a Vauxhall Insignia with Stop/Start and now a Jazz Mk3 with it and it never bothers or causes me any issues at all. Why turn it off!!!
Title: Re: Idle stop, on or off?
Post by: Skyrider on April 16, 2017, 01:26:51 PM
If turning off my stop start is not effecting my fuel consumption how can it be effecting the cars emissions? 
Title: Re: Idle stop, on or off?
Post by: peteo48 on April 16, 2017, 02:13:18 PM
If turning off my stop start is not effecting my fuel consumption how can it be effecting the cars emissions?

I think it's the concentration of fumes at pavement level that is the issue here rather than the global total. Idling traffic does kick out a lot of stuff that can be breathed in by pedestrians or even other road users through the ventilation system so it's why people are often recommended to switch to recirculate mode when in heavy traffic.
Title: Re: Idle stop, on or off?
Post by: Downsizer on April 16, 2017, 02:45:28 PM
I think the vehicles accelerating away from the lights emit many times more pollution than those waiting.  However, "every little helps" I suppose.
Title: Re: Idle stop, on or off?
Post by: guest6570 on April 16, 2017, 02:47:58 PM
If turning off my stop start is not effecting my fuel consumption how can it be effecting the cars emissions?

Your car burns fuel when idling and stop start is disabled therefore it will burn some be it miniscule amount of fuel and contribute to CO2 emissions into the atmosphere. Maybe not harmful if it is just one car but take into account all the millions of cars on the road then it becomes a much bigger issue. And if the manufacturers didn't include stop start on Cars then your road tax would be higher depending on which band of tax your car falls into. Would you rather pay more car tax! Like I said I don't find the Jazz stop start to be any problem at all but each to their own!
Title: Re: Idle stop, on or off?
Post by: Skyrider on April 16, 2017, 03:04:55 PM
I have done my bit by switching from diesel to petrol. I also live in a low traffic semi rural area where my car is only occasionally stationary for a few seconds at a time.....when it is in use.  :-)
Title: Re: Idle stop, on or off?
Post by: culzean on April 17, 2017, 01:04:55 PM
I have done my bit by switching from diesel to petrol. I also live in a low traffic semi rural area where my car is only occasionally stationary for a few seconds at a time.....when it is in use.  :-)

Two of my brothers were lifetime diesel fans and they have switched to petrol and were surprised how far petrol engines have advanced and how quiet and nice to drive they are.

Their only worry is putting diesel in instead of petrol.  I would have thought with todays technology a vehicle would have a chip by the filler to match with chip on fuel nozzle to stop people putting wrong fuel in.
Title: Re: Idle stop, on or off?
Post by: Skyrider on April 17, 2017, 01:15:19 PM
The diesel pump nozzle is a larger diameter than a petrol one, petrol in a diesel is easy, a diesel nozzle does not fit in most petrol cars. I owned diesels for 30odd years, never a problem, I always cross checked nozzle, pump indication, and price. The jazz is a doddle, the diesel nozzle doesn't fit!
Title: Re: Idle stop, on or off?
Post by: ColinS on April 17, 2017, 01:15:36 PM
Their only worry is putting diesel in instead of petrol.  I would have thought with todays technology a vehicle would have a chip by the filler to match with chip on fuel nozzle to stop people putting wrong fuel in.
The diesel nozzle is generally bigger than the petrol nozzle so shouldn't be an issue that way round.
Title: Re: Idle stop, on or off?
Post by: Jocko on April 17, 2017, 04:19:26 PM
I drive a diesel van, so have to be very careful when filling that up. After 50 years of buying petrol I wonder how long it will be before I make the mistake!
Title: Re: Idle stop, on or off?
Post by: andruec on April 17, 2017, 07:28:18 PM
Idle stop might improve fuel consumption (slightly). It might reduce pavement level pollution (slightly).

But what it does not do (or only very rarely) is interfere with my use of the vehicle. Therefore I allow it to do its thing. If other drivers are struggling to live with it I can only suggest that they learn how to operate their vehicle properly. My engine is always on and ready to go when I need it. It may or may not be running when I don't need it but I don't care either way about that.

Perhaps if those that don't like it can explain what the problem is the rest of us can tell them what they are doing wrong.
Title: Re: Idle stop, on or off?
Post by: ColinB on April 18, 2017, 10:01:16 AM
I have been turning my idle stop off for a couple of weeks,....This makes normal driving with short stops far more pleasant ...
... these systems detract from driving comfort and pleasure ...
... I have been passenger in stop-start cars and I reckon I would be switching it off as well if I was driving.
I don't understand these comments. Could you guys explain why it is somehow "unpleasant" ? The guy in the video talks about it being harsh on restart (in some cars), but mine operates seamlessly without any fuss and is barely noticeable. Certainly it's not annoying enough to make me want to remember to turn the system off every time I start the car. Does yours do something intrusive or uncomfortable ? Although if you have CVTs then I'd encourage you to turn it off so you don't dazzle the driver behind with your brake lights, that's definitely more annoying than whether it may or may not save a minuscule amount of fuel & emissions.
Title: Re: Idle stop, on or off?
Post by: richardfrost on April 18, 2017, 10:18:11 AM
Although if you have CVTs then I'd encourage you to turn it off so you don't dazzle the driver behind with your brake lights

That is nothing to do with Stop/Start and everything to do with Brake Hold. Just pull up the Handbrake button and the brake lights will go off. Brake Hold is like keeping your foot on the foot brake. It is not the Hand Brake. Or is that different on a CVT?
Title: Re: Idle stop, on or off?
Post by: ColinB on April 18, 2017, 03:04:48 PM
Although if you have CVTs then I'd encourage you to turn it off so you don't dazzle the driver behind with your brake lights

That is nothing to do with Stop/Start and everything to do with Brake Hold. Just pull up the Handbrake button and the brake lights will go off. Brake Hold is like keeping your foot on the foot brake. It is not the Hand Brake. Or is that different on a CVT?
I'm not a CVT driver, but my understanding (from comments in other threads on this forum) is that Start-Stop on a CVT (and indeed autos from other manufacturers) is governed by the foot brake. The engine only remains stopped if the driver has his foot on the brake irrespective of whether the handbrake is on or off. Lift off the brake pedal and the engine restarts. So the brake lights stay on if the driver wants the engine to stay stopped, and hence my comment that I'd be happy for CVT drivers to switch the system off. No, I don't understand why it's designed that way either. Happy to be corrected by any CVT driver out there.
PS I don't think the Jazz has "brake hold".
Title: Re: Idle stop, on or off?
Post by: Downsizer on April 18, 2017, 04:30:53 PM
Colin B is correct about CVT.  As soon as you take your foot off the brake, the engine restarts, regardless of the handbrake.  If it wasn't so, there would be no signal to restart I suppose.
Title: Re: Idle stop, on or off?
Post by: richardfrost on April 19, 2017, 08:36:05 AM
Interesting. I drive a manual H-RV and I guess I assumed it was based on the Jazz.
Title: Re: Idle stop, on or off?
Post by: Skyrider on April 19, 2017, 09:01:39 AM
Interesting. I drive a manual H-RV and I guess I assumed it was based on the Jazz.

It is, (a Jazz on stilts  :D ) but as yours is a diesel it will have a totally different engine management system.
Title: Re: Idle stop, on or off?
Post by: andruec on April 19, 2017, 03:09:03 PM
Happy to be corrected by any CVT driver out there.
PS I don't think the Jazz has "brake hold".
You're correct about the CVT and Idle Stop issue. It annoyed me at first but so many people do keep the foot brake pressed when stationary (regardless of transmission) these days that I've learnt to accept it. It never really dazzled me so I'm happy to take the view that if you really are being dazzled you should go to an optician :)

What irritates me most about the CVT I/S implementation is that the engine restarts even if you've selected neutral before releasing the brake pedal. The silly thing is that it will restart if you move the selector out of N so in that case there is a perfectly good indication that you want to move.

As for how much fuel it saves the last time I looked on the web most technical sites were saying that as long as the engine is off for at least two seconds it will save something. Estimates vary but in several 'real world' tests I found it seemed to about five to ten percent for urban driving. That equates to reducing the price of a litre of petrol by 5p or more and I bet most of us would consider that worthwhile :)

However you're wrong about 'brake hold'. My EX has it.

Edit: Re, idle fuel consumption https://energy.gov/eere/vehicles/fact-861-february-23-2015-idle-fuel-consumption-selected-gasoline-and-diesel-vehicles

For a 2 litre petrol engine it's claiming .16 gallons an hour or .6 litres an hour. So that's just over 1p a minute. So very approximately I/S could be saving me £2 a year. Hardly worth worrying about. But if we multiply that by the couple of hundred thousand vehicles on the road that have this feature (assuming most leave it on) and the fuel savings become more significant.
Title: Re: Idle stop, on or off?
Post by: peteo48 on April 19, 2017, 04:31:49 PM
I have been turning my idle stop off for a couple of weeks,....This makes normal driving with short stops far more pleasant ...
... these systems detract from driving comfort and pleasure ...
... I have been passenger in stop-start cars and I reckon I would be switching it off as well if I was driving.
I don't understand these comments. Could you guys explain why it is somehow "unpleasant" ? The guy in the video talks about it being harsh on restart (in some cars), but mine operates seamlessly without any fuss and is barely noticeable. Certainly it's not annoying enough to make me want to remember to turn the system off every time I start the car. Does yours do something intrusive or uncomfortable ? Although if you have CVTs then I'd encourage you to turn it off so you don't dazzle the driver behind with your brake lights, that's definitely more annoying than whether it may or may not save a minuscule amount of fuel & emissions.

I'll come clean here. I have no experience of the Honda Stop Start but my daughter's Qashqai has it and it seems a bit clunky. It's on a manual though.
Title: Re: Idle stop, on or off?
Post by: andruec on April 19, 2017, 04:58:21 PM
The Jazz (at least mine) there is just a slight tremble when it starts back up.

The only real issue I have - and I blame myself - is if I misjudge the traffic at a roundabout and come to a halt unnecessarily. If I realise my mistake I might end up pressing the accelerator at the same time as the engine is shutting off. Obviously there's an annoying delay in that situation. It doesn't happen very often though and I blame myself for misjudging the traffic flow.

But in normal use the engine restarts about as fast as I can move my foot from brake to accelerator so it doesn't cause a problem.
Title: Re: Idle stop, on or off?
Post by: Skyrider on April 19, 2017, 09:11:14 PM
You don't realise how intrusive the engine restart is until you turn off the idle stop system. Unless you have no mechanical sympathy and are totally insensitive.  :-)
Title: Re: Idle stop, on or off?
Post by: ColinB on April 19, 2017, 11:54:28 PM
However you're wrong about 'brake hold'. My EX has it.
Really ? Could you describe how you use it please ? Are you perhaps confusing Brake Hold (as described here http://www.jthughes.co.uk/How-To/View/Honda/HR-V/How-to-use-the-Honda-HR-V-brake-hold-option/02279019-149f-47ba-b05b-e589bb30b9ee (http://www.jthughes.co.uk/How-To/View/Honda/HR-V/How-to-use-the-Honda-HR-V-brake-hold-option/02279019-149f-47ba-b05b-e589bb30b9ee)) with Hill Start Assist ? I don't see BH listed as a feature on any Jazz spec, but HSA is.
Title: Re: Idle stop, on or off?
Post by: Kenneve on April 20, 2017, 10:27:16 AM
My stop/start system is always On, but rarely operates because in normal stops, the brake pedal is not pressed hard enough to trigger the function. On the odd occasion when it does trigger, it restarts the instant I take my foot off the brake, as I would expect.
Title: Re: Idle stop, on or off?
Post by: andruec on April 20, 2017, 01:39:04 PM
However you're wrong about 'brake hold'. My EX has it.
Really ? Could you describe how you use it please ? Are you perhaps confusing Brake Hold (as described here http://www.jthughes.co.uk/How-To/View/Honda/HR-V/How-to-use-the-Honda-HR-V-brake-hold-option/02279019-149f-47ba-b05b-e589bb30b9ee (http://www.jthughes.co.uk/How-To/View/Honda/HR-V/How-to-use-the-Honda-HR-V-brake-hold-option/02279019-149f-47ba-b05b-e589bb30b9ee)) with Hill Start Assist ? I don't see BH listed as a feature on any Jazz spec, but HSA is.
Ah, yes. Sorry.
Title: Re: Idle stop, on or off?
Post by: Downsizer on April 20, 2017, 04:23:51 PM
Really ? Could you describe how you use it please ? Are you perhaps confusing Brake Hold (as described here http://www.jthughes.co.uk/How-To/View/Honda/HR-V/How-to-use-the-Honda-HR-V-brake-hold-option/02279019-149f-47ba-b05b-e589bb30b9ee (http://www.jthughes.co.uk/How-To/View/Honda/HR-V/How-to-use-the-Honda-HR-V-brake-hold-option/02279019-149f-47ba-b05b-e589bb30b9ee)) with Hill Start Assist ? I don't see BH listed as a feature on any Jazz spec, but HSA is.
I hadn't heard of the Brake Hold feature before.  It sounds rather useful, and I would welcome it on the Jazz.  It seems to operate in conjunction with the electronically operated handbrake.
Title: Re: Idle stop, on or off?
Post by: ColinB on April 20, 2017, 05:43:35 PM
However you're wrong about 'brake hold'. My EX has it.
Really ? Could you describe how you use it please ? Are you perhaps confusing Brake Hold (as described here http://www.jthughes.co.uk/How-To/View/Honda/HR-V/How-to-use-the-Honda-HR-V-brake-hold-option/02279019-149f-47ba-b05b-e589bb30b9ee (http://www.jthughes.co.uk/How-To/View/Honda/HR-V/How-to-use-the-Honda-HR-V-brake-hold-option/02279019-149f-47ba-b05b-e589bb30b9ee)) with Hill Start Assist ? I don't see BH listed as a feature on any Jazz spec, but HSA is.
Ah, yes. Sorry.
It's very tempting to suggest that if you are having trouble seeing the dashboard buttons and indicators ...
... you should go to an optician :)
But I wouldn't go quite that far. :D :D :D
Title: Re: Idle stop, on or off?
Post by: John Ratsey on April 20, 2017, 10:17:27 PM
I like the principle of the idle stop although I was spoiled because I first encountered it on the Jazz hybrid which has a very smooth restart due to the electric motor. However, the idle stop on the Mk 3 Jazz (or my current HR-V) is no problem provided one remembers a couple of points (i) anticipate the need to move by about a second by reducing the brake pedal pressure (which restarts the engine on the CVT vehicles) and (ii) light brake pedal pressure will stop the car but not the engine which is appropriate for roundabout queues whereas the idle stop is appropriate for traffic light queues. But I much prefer driving in conditions where the traffic keeps moving and the idle stop isn't needed ;D
Title: Re: Idle stop, on or off?
Post by: andruec on April 21, 2017, 08:56:59 AM
But I much prefer driving in conditions where the traffic keeps moving and the idle stop isn't needed ;D
Yeah. I've become quite adept at controlling it at roundabouts. Banbury rush hour varies quite a lot and it takes experience to work out if a queue is slow moving or 'stuck'. Sometimes a long queue for a roundabout is slow moving. Sometimes a short queue is stuck.

The trick on this stretch (https://www.google.co.uk/maps/@52.0722122,-1.3208304,3a,75y,62.03h,90.7t/data=!3m6!1e1!3m4!1sBArFp8iLlrBoWZdV27wfVw!2e0!7i13312!8i6656?hl=en) is to look out for pedestrians hovering around the traffic lights. The naughty monkeys sometimes press the button. How jolly inconsiderate of them :D

I like to let I/S do it's thing but I have to be sure that it will be off for at least 2 seconds to avoid wasting fuel. Still - it all adds to the fun of driving in my view :)
Title: Re: Idle stop, on or off?
Post by: Skyrider on April 30, 2017, 03:57:56 PM
This weekend I have done a round trip of 350 miles, near the end of the outbound journey I was involved in heavy traffic and the stop start gave a low battery, not working indication. I left the stop start switched on until I returned home and the system continued with low battery indications. I disconnected the battery earth connection for about 15 minutes and on reconnection normal service has been resumed. It seems the car had lost the plot on battery charge level but it only seemed to affect the stop start.
Title: Re: Idle stop, on or off?
Post by: ColinB on April 30, 2017, 06:59:22 PM
I find that the reason for the system not operating when you expect it to is not necessarily related to the indication you get. For example, it won't operate if you have the ventilation set to the demist (screen) setting, but the indication will say "A/C" irrespective of whether the A/C is operating or not. And as I discovered during very cold weather, it won't operate if the battery temperature is too low, but the indication was "low battery" rather than "low temperature". Not necessarily suggesting either of these apply in your circumstances, just that the reason might not be the one you expect from the indication. And as you've commented yourself in another thread, trying to work out why it's not working when there are so many arcane reasons is tricky.
Title: Re: Idle stop, on or off?
Post by: Skyrider on April 30, 2017, 07:18:36 PM
I agree that the stop start operation is a bit of magic and mirrors, but mine did not work for the whole 350 mile journey which included half way coffee stops and being parked for 36 hours at the destination. The weather was mild and the aircon was on throughout. The mpg was 55 full to full which surprised me as I was not hanging about and running at the 60 and 70 limits and using the full rev range when accelerating.
Title: Re: Idle stop, on or off?
Post by: Skyrider on May 07, 2017, 12:04:01 PM
While checking the user manual to remind myself of the multitude of instrument indicators I discovered that my stop start not working was self inflicted. On page 110 it explains that the stop start may not work with a battery low indication shown after charging the battery or jump starting the car. This may be overcome by driving the car or if this does not work disconnect the battery -ve connection and reconnect it. I had put the battery on charge the day before the problem. As I had guessed the car had lost the battery charge level and a reset fixed it. The car seems to be running smoother since the reset but that is a whole different can of worms.  :-)
Title: Re: Idle stop, on or off?
Post by: andruec on May 07, 2017, 07:33:18 PM
Why did you feel the need to put your battery on charge? I haven't done that in nearly thirty years of motoring.
Title: Re: Idle stop, on or off?
Post by: Skyrider on May 07, 2017, 07:47:40 PM
For much of my working life I was involved with very big lead acid batteries and their maintenance.  An equalising charge  every three months or so does no harm and I have not had a car battery fail in over fifty years.
Title: Re: Idle stop, on or off?
Post by: culzean on May 07, 2017, 08:31:51 PM
For much of my working life I was involved with very big lead acid batteries and their maintenance.  An equalising charge  every three months or so does no harm and I have not had a car battery fail in over fifty years.

True, an equalising charge every so often will keep a battery healthy and 'equalise' the cell voltages and remove any slight sulphation that is building up due to imbalance in chemical reactions in battery.  Some people think batteries do not need any maintenance and are 'surprised' when a neglected battery fails and they blame the battery.
Title: Re: Idle stop, on or off?
Post by: Skyrider on May 08, 2017, 09:32:50 AM
Ever wondered why Halfords and other motoring outlets keep a range of batteries in stock? Maintenance free? Aye right! The maintenance free claim comes from a vapour trap in the cell vents which help maintain the electrolyte level. And marketing of course. :-)

Many small battery powered devices instructions recommend an extended charge before first use. This is because the device will indicate "charged" when the first cell of the battery is charged. The extended charge fully charges all the battery cells and improves battery performance having equalised their output.
Title: Re: Idle stop, on or off?
Post by: andruec on May 08, 2017, 11:41:34 AM
Well that's interesting to know but I've never had a battery fail on me. I had to replace one once after six years because it was clearly beginning to struggle a bit starting the car when cold but that's all. It might be marketing hype but my personal experience is that 'maintenance free' means exactly that. Of course I've never owned any vehicle longer than six or seven years but honestly I'd be shocked and disgusted if any current model Jazz needed anything doing to its battery. Mine happens to get a good workout almost every day but my Dad's and his companion's cars (not Hondas) can go several days without being used and when used are only driven two miles into town and back. Neither of them have had any problems. My Dad had to replace his C2 after running into a deer last year. Three years old and I think he said it 5,000 miles on it. That included it being used by all of us for a week long trip from North Wales to Dumfries and Galloway last summer.

An 'unmaintained' battery might not be in perfect condition and maybe it won't last as long as it might. But I don't think it's anything any of us have to worry about for several years and I reckon most of us will have passed our vehicles onto someone else before the problems start. Of course the batteries in our cars are a different design and getting more work because of Idle Stop so that might have an impact. But I have faith in Honda when it comes to the important mechanical bits. I'm happy to ignore the problem and leave it to whoever is driving my car in the late 2020s ;)
Title: Re: Idle stop, on or off?
Post by: Skyrider on May 08, 2017, 04:37:42 PM
Honda seem to consider the battery as a wear and tear item. There are instructions for charging and changing the battery in the user manual. Some of us are impoverished pensioners who can't afford a new car every couple of years. :-)
Title: Re: Idle stop, on or off?
Post by: Paulwhitt20 on May 08, 2017, 09:48:45 PM
I thought maintenance free batteries just meant you did not have to top them up with distilled water every so often.
Title: Re: Idle stop, on or off?
Post by: Skyrider on May 09, 2017, 07:01:58 AM
I thought maintenance free batteries just meant you did not have to top them up with distilled water every so often.

That is correct, most "maintenance free" batteries have a sticker or a glued down cap across the top which covers the cell filling caps. As I said above, the cell vents have vapour traps which reduces the electrolyte loss and the requirement to top up with distilled water.
Title: Re: Idle stop, on or off?
Post by: andruec on May 17, 2017, 07:47:19 PM
How much are replacement batteries for the Jazz? It was £50 for my last Jazz and since it lasted the entire four+ years I owned the vehicle doesn't sound very expensive. Of course if you can make a battery last longer then good for you and good for the environment. It just sounds like too much hassle to me if you're triggering warnings from the vehicle by doing it.
Title: Re: Idle stop, on or off?
Post by: Kenneve on May 31, 2017, 05:03:44 PM
I'm a bit surprised that other members find the Stop/Start feature a hassle.
In my normal driving mode, it almost never actuates, unless I brake to a stop heavily and even then the pedal pressure has to maintained, very much over what would be required, simply to hold the car stationary.
Of course, if you are stationary at traffic light for example, then the car should be in neutral, with the handbrake on, to avoid blinding the driver behind you.
Title: Re: Idle stop, on or off?
Post by: andruec on May 31, 2017, 06:07:27 PM
Of course, if you are stationary at traffic light for example, then the car should be in neutral, with the handbrake on, to avoid blinding the driver behind you.
Sadly not possible with the CVT version. The engine will always restart when you release the brake pedal regardless of what position the gear selector is in. It's common across all automatic vehicles with automatic gearboxes. I've no idea why but unfortunately with automatics if you want to keep the engine off while stationary you have to keep your foot on the brake pedal :-/
Title: Re: Idle stop, on or off?
Post by: Skyrider on June 24, 2017, 08:18:41 PM
I have found another reason to disable the stop start. During the recent mini heat wave when the car registered an external temperature of 34°C on four consecutive days and I was using the car a lot, it keeps the aircon working.
Title: Re: Idle stop, on or off?
Post by: ColinS on June 24, 2017, 09:47:39 PM
I have found another reason to disable the stop start. During the recent mini heat wave when the car registered an external temperature of 34°C on four consecutive days and I was using the car a lot, it keeps the aircon working.
The system is designed so that if the cabin temperature is high and requires aircon to cool it, then the engine will not stop.  At least that is how mine worked during the hot weather.
Title: Re: Idle stop, on or off?
Post by: mikebore on June 25, 2017, 10:59:08 AM
If turning off my stop start is not effecting my fuel consumption how can it be effecting the cars emissions?

Your car burns fuel when idling and stop start is disabled therefore it will burn some be it miniscule amount of fuel and contribute to CO2 emissions into the atmosphere. Maybe not harmful if it is just one car but take into account all the millions of cars on the road then it becomes a much bigger issue. And if the manufacturers didn't include stop start on Cars then your road tax would be higher depending on which band of tax your car falls into. Would you rather pay more car tax! Like I said I don't find the Jazz stop start to be any problem at all but each to their own!

I think also the benefit of idle stop is localised in urban high traffic density areas, rather than global.

Ooops just realised I have just replied to an old post ::)
Title: Re: Idle stop, on or off?
Post by: mikebore on June 25, 2017, 11:05:19 AM
I have found another reason to disable the stop start. During the recent mini heat wave when the car registered an external temperature of 34°C on four consecutive days and I was using the car a lot, it keeps the aircon working.

I have discovered this as well.

With all the situations that Honda have found to automatically disable idle stop, they might have included this one. Mine works like Deeps's not ColinS's.

BTW, I vaguely remember a comment earlier that idle stop/start was noticeable and unpleasant for occupants. We really don't find this at all, just barely noticeable, unlike in my brother in laws Audi A6 diesel, where the auto stop/start is very obtrusive.
Title: Re: Idle stop, on or off?
Post by: ColinS on June 25, 2017, 12:11:24 PM
I have found another reason to disable the stop start. During the recent mini heat wave when the car registered an external temperature of 34°C on four consecutive days and I was using the car a lot, it keeps the aircon working.

I have discovered this as well.

With all the situations that Honda have found to automatically disable idle stop, they might have included this one. Mine works like Deeps's not ColinS's.

BTW, I vaguely remember a comment earlier that idle stop/start was noticeable and unpleasant for occupants. We really don't find this at all, just barely noticeable, unlike in my brother in laws Audi A6 diesel, where the auto stop/start is very obtrusive.

That is very strange.  Mine actually displays A/C as a reason for it not activating.  My model has "climate control", perhaps that is the difference.
Title: Re: Idle stop, on or off?
Post by: andruec on June 25, 2017, 06:29:07 PM
I have found another reason to disable the stop start. During the recent mini heat wave when the car registered an external temperature of 34°C on four consecutive days and I was using the car a lot, it keeps the aircon working.
The system is designed so that if the cabin temperature is high and requires aircon to cool it, then the engine will not stop.  At least that is how mine worked during the hot weather.
Same here. The fan will sometimes drop down to three when idle stop kicks in but it doesn't impact cabin temperature much. Mostly it just put up the 'AC' symbol. For what's it's worth mine also has climate control.

As I think I've posted before - I've been critical of many features of the Jazz but idle stop seems to do exactly what it should and is very unobtrusive. I consider it the best feature of the Jazz.

We've now got roadworks (again! FFS!) at 'my' roundabout on Southam road, Banbury. Aside from the irritation of an extra ten minutes added to my commute each way the impact on fuel consumption is noticeable. Idle stop does its best in the morning but often the lights take so long to cycle that it gives up and restarts the engine. In the evenings the engine is just not warm enough to allow idle stop to function. The result is that my fuel consumption has dropped from around 58mpg to 51mpg (measured pump to pump). You can see the impact in the morning when I/S finally gives up. Suddenly the displayed MPG starts to drop by about .1 very 30 seconds :(

As for why they couldn't just do the job properly last when they dug the roundabout (https://www.google.co.uk/maps/@52.0819261,-1.3350686,197m/data=!3m1!1e3?hl=en) up....we all knew about the additional houses. They must have. Why only connect one group when six months later another group was due to start construction. Idiots.
Title: Re: Idle stop, on or off?
Post by: guest1372 on June 26, 2017, 12:21:53 AM
I'm going to post later about the new Audi A8 (launches next month) a couple of my friends have been involved with developing; that uses it's front camera and location to augment the idle stop.  This car knows if you are at a roundabout,  at traffic lights or in queuing traffic - when the car ahead moves forward it starts the engine while the brake is still pressed.  It also effectively uses a bit of start/stop technology while you are coasting or decelerating. 
--
TG
Title: Re: Idle stop, on or off?
Post by: Downsizer on June 26, 2017, 04:07:48 PM
That is very strange.  Mine actually displays A/C as a reason for it not activating.  My model has "climate control", perhaps that is the difference.
On my SE with no climate control, the A/C keeps going but the engine stops.  However, it restarts during a prolonged hold-up as you would expect to protect the battery.
Title: Re: Idle stop, on or off?
Post by: andruec on June 26, 2017, 04:35:19 PM
I'm going to post later about the new Audi A8 (launches next month) a couple of my friends have been involved with developing; that uses it's front camera and location to augment the idle stop.  This car knows if you are at a roundabout,  at traffic lights or in queuing traffic - when the car ahead moves forward it starts the engine while the brake is still pressed.  It also effectively uses a bit of start/stop technology while you are coasting or decelerating. 
--
TG
Audi have some cool tech. The smart matrix headlights are really neat - no need for them to switch off main beam, just dim those elements pointing directly at the oncoming traffic. It's just a shame so many of the drivers are aggressive speed merchants :(
Title: Re: Idle stop, on or off?
Post by: Skyrider on June 27, 2017, 07:56:24 AM
That is very strange.  Mine actually displays A/C as a reason for it not activating.  My model has "climate control", perhaps that is the difference.
On my SE with no climate control, the A/C keeps going but the engine stops.  However, it restarts during a prolonged hold-up as you would expect to protect the battery.

The ventilation fan keeps running but the aircon compressor is engine driven, so no aircon when the engine is stopped.
Title: Re: Idle stop, on or off?
Post by: andruec on June 27, 2017, 08:51:59 AM
That is very strange.  Mine actually displays A/C as a reason for it not activating.  My model has "climate control", perhaps that is the difference.
On my SE with no climate control, the A/C keeps going but the engine stops.  However, it restarts during a prolonged hold-up as you would expect to protect the battery.

The ventilation fan keeps running but the aircon compressor is engine driven, so no aircon when the engine is stopped.
Yeah, so exactly what happens will depend on what cycle the A/C is in. Sometimes mine just drops the fan a bit, other times it puts up the (AC) indicator. This morning was impressive though. I saw the temporary lights turn red as they came into view so I coasted (in gear, but not accelerator) the half a mile to them. It clearly annoyed the Mercedes driver behind me but that's not my problem. Traffic was light so I wasn't causing more queuing. Despite my efforts we still had to stop eventually and we were stationary for long enough for an entire song to play on my iPod. But the Idle Stop allowed the engine to stay off for the whole time.

Maybe it taught the Mercedes driver something..but I doubt it. They probably think I delayed them.
Title: Re: Idle stop, on or off?
Post by: John Ratsey on June 27, 2017, 10:35:29 AM
I'm a believer that the auto stop does reduce fuel wasted and I get grumpy when it doesn't work (usually low battery). The HR-V handbook specifically notes that using the Eco mode increases the allowable temperature deviation from the target (which reduces the need for the engine to restart just for cabin heating / cooling). The same may apply on the Mk 3 Jazz although I don't recall it being mentioned in the book.