ICE stop start

[Penfold72]

I've just been wondering if constantly having the ICE starting and stopping can do any damage. For instance, I can be cruising along with Battery power, but the ice kicks in, but only for a few seconds if I then brake etc. This can happen to me quite a lot if running in slowish traffic, mainly on Battery, but if I need to speed up ice kicks in, but then is stopped again as I slow down and regenerative braking occurs. Just something I've mulled over.....

[Haliotis]

During development of the stop/start function for ICE, I would think that manufacturers exhaustively proved their design through R&D procedures and by lengthy road-testing.   I have never read anywhere of this feature being reported as disadvantageous to engine/transmission wear.

[philip42h]

1 hour ago, Penfold72 said:

I've just been wondering if constantly having the ICE starting and stopping can do any damage.

In a word, 'no'.

I am assuming here that we are talking about the Toyota hybrid engine? In which case it is very much a part of the design and has been proven over the decades now. Specifically, the engine will start towards the beginning of your journey and run until it is warm and the oil is circulated 'everywhere'. It will then restart frequently thus maintaining that 'good to go' status. Empirical evidence - i.e. lack of reported engine failures - suggests that the design is just fine.

[Penfold72]

Thanks for the replies. I do worry about nothing 😳. 

[Cyker]

It's only a problem if the engine's cold, but the engine won't stop if it's cold, it'll keep running until it reaches minimum operating temperature.

Once it's warm, it's fine for it to start and stop, and if it isn't the car will run the engine longer. It's pretty smart.

It can be a bit perplexing as it just seems to do stuff at random, but you learn to ignore it and let it get on with managing itself while you concentrate on driving!

[Penfold72]

Thanks. Only thing I've noticed is it doesn't like to be shutoff with the engine running. It's only happened on a couple of occasions where I've driven really short distance due to hammering rain, and engine has kicked in. It does shut off with a bit of a *****. 😕

[Cyker]

My Yaris does that too; I vaguely recall someone saying they usually wait for the engine to shut off naturally before turning the car off, but I don't got time for dat!  

[TonyHSD]

11 minutes ago, Penfold72 said:

Thanks. Only thing I've noticed is it doesn't like to be shutoff with the engine running. It's only happened on a couple of occasions where I've driven really short distance due to hammering rain, and engine has kicked in. It does shut off with a bit of a *****. 😕

It’s not a good idea to switch off the car when the engine is running for whatever reason is. Best to wait to finish its work and then turn it off. 
If you don’t want to wait and engine is running because of anything else but recharging the Battery you can turn off your hvac fan , the engine will immediately turn off too and then you can switch off the system via the stop stat button. 👍

[Penfold72]

I assume HVAC means the climate control. Only 4 months in with a hybrid, still getting used to their quirks after my normal diesel SUV. 

[Cyker]

It's a catchall term for anything to do with Heating, Ventilation and Air Conditioning

 

[Haliotis]

I don’t know what the stop/start criteria is for my hybrid but, for my previous car (VW automatic with DSG gearbox), the operation of the stop/start activating or not depended on several factors - engine temperature/state of battery/ambient temperature, and possibly other factors.

What was common is, when I applied the brake and came to a stop, if the engine did stop and I moved the gear lever to neutral, the engine would restart regardless of any other factors.

But I would imagine some of the factors in my VW also apply for a hybrid car.

[Cyker]

The basic trigger is if the engine gets bored (e.g. not enough load) it'll go to sleep and palm the work off onto MG2 (The drive electric motor). If MG2 can't cope it passes it back on to the ICE.

There are other things - Heat, B-mode, GPF regen to name a few, but that's the main thing.

 

[TonyHSD]

5 hours ago, Haliotis said:

I don’t know what the stop/start criteria is for my hybrid but, for my previous car (VW automatic with DSG gearbox), the operation of the stop/start activating or not depended on several factors - engine temperature/state of battery/ambient temperature, and possibly other factors.

What was common is, when I applied the brake and came to a stop, if the engine did stop and I moved the gear lever to neutral, the engine would restart regardless of any other factors.

But I would imagine some of the factors in my VW also apply for a hybrid car.

Toyota hybrids has very little in common with other makes hybrids and works on very different principles. Toyota ones are unique system that both power sources work almost always together and help each other. The system switches between ice and ev many times even in a short travel. They does have pure ev range unless they are plug is hybrids, the engines doesn’t work as generator only but also propel the car and provides heat. There are many videos on YouTube and they are interesting to watch. More you learn about this technology more you understand how good they are and why they might be better than pure electric cars by all means. 

[Haliotis]

When I have logged onto MyT and  looked at the Hybrid Coaching data, The switching between ICE and EV is quite obvious.    It is very tempting to “play” with the acceleration/braking/coasting to later see how much percentage of EV can be achieved for short journeys.  The best I have obtained is almost 100% EV for a journey of about 3 miles.

[Penfold72]

I've tried this as, well, and managed 100% electric travel short distances, although engine has to be warm and Battery relatively full. Didn't manage 3 miles though 😟

[Haliotis]

Looking at the MyT road map for the trip, there were a few very small blips where the ICE had cut in but, when I switched off the at the end of this journey, the MFD showed 100% EV.  The driving skill showed 74/100 for this thrip.

For a while I tried to achieve 100% driving skill, or near to it, but my best is in the upper 80’s.   I have never been heavy on accelerator or brakes, yet the record has indicated hard braking (red car symbol) when there was no such thing.  To be honest, I now rarely bother with the Hybrid Coaching info as I regard it as a gimmick, rather than a useful tool.

[TonyHSD]

Toyota hybrids should not be used as evs especially on cold. Transmission has an oil pump that is driven by the petrol engine and pure ev drive on cold means your transmission bearings and electric motor has no proper lubrication. 
To see for yourself, start the car on cold , hit the ev button and then turn the fan off,  select D and start driving slowly in ev mode only you can hear whining from the transmission like bad differential or bad bearings especially if you go uphill it’s very pronounced.  This is because your transmission bearings are dry. The splash lubrication is mainly for the gears but the bearings and mg2 are spinning dry and they do spin a lot faster usually 1:10 ratio. 

[JCT-DK]

So it’s better when cold to drain the Battery and start off on ICE?

Or it’s only when you start off in pure EV by pressing the EV button?

I mean in most situations there is some Battery left from the prior drive and when starting off next time cold the car drives on EV before the ICE kicks in and charges the battery/ warning up.

This would be alright ?

[philip42h]

1 hour ago, TonyHSD said:

Toyota hybrids should not be used as evs especially on cold. Transmission has an oil pump that is driven by the petrol engine and pure ev drive on cold means your transmission bearings and electric motor has no proper lubrication. 
To see for yourself, start the car on cold , hit the ev button and then turn the fan off,  select D and start driving slowly in ev mode only you can hear whining from the transmission like bad differential or bad bearings especially if you go uphill it’s very pronounced.  This is because your transmission bearings are dry. The splash lubrication is mainly for the gears but the bearings and mg2 are spinning dry and they do spin a lot faster usually 1:10 ratio. 

I'm not sure that is entirely true Tony ...

The current eCVT "transaxle has a new ring gear-driven oil pump, which provides lubrication for both the gears and motor/generator units." Which I suspect means that it is in effect driven via MG1 as required? I could be entirely wrong of course ... 😉 

[Cyker]

1 hour ago, JCT-DK said:

So it’s better when cold to drain the battery and start off on ICE?

Or it’s only when you start off in pure EV by pressing the EV button?

I mean in most situations there is some battery left from the prior drive and when starting off next time cold the car drives on EV before the ICE kicks in and charges the battery/ warning up.

This would be alright ?

TBH it's best to not worry about it and let the car handle it - It has all sorts of parameters for optimal running and will do what it needs to.

Just drive the car (NB: Like a normal person and not a crazed maniac) and it'll take care of itself!

[TonyHSD]

1 hour ago, philip42h said:

I'm not sure that is entirely true Tony ...

The current eCVT "transaxle has a new ring gear-driven oil pump, which provides lubrication for both the gears and motor/generator units." Which I suspect means that it is in effect driven via MG1 as required? I could be entirely wrong of course ... 😉 

That’s exactly the new ring gear pump since 2010 gen 3 hybrids and the guy from Weber auto has shown on. Your car is slightly different though as it has pure ev mode because it’s phev. 

[Roy124]

4 hours ago, JCT-DK said:

most situations there is some battery left from the prior drive and when starting off next time cold the car drives on EV before the ICE kicks in and charges the battery/ warning up.

It depends. 

If the car is cold, in my case reversing out of the garage, I can switch off the conditioning and reverse out of the garage on EV.  Sitting, waiting for SWMBO, the ICE will kick in when the car decides the HV needs a boost.

When it's much colder, regardless of what I do,  the ICE will kick in.

The Car Care Nut covers this well.  A conventional ICE water pump pumps cold water round the system and continues until the water is up to temp.  In the Corolla,  and I guess other Toyota, circulation is limited to where it will heat up quickly and only circulate to less important parts once hot.

Yes, just let the car do its thing.

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