Yaris Hybrid - ICE running most of the time

[Yaris2022]

Hi everyone,

 

I have a 2021 Yaris Hybrid, and everything is good with the car, however, for a few weeks now, the car engine is running more than it used to, and the EV light will stay out unless I come to a complete stop.

When I do stop, the engine will shut off and the EV light will come on, but when I then accelerate into the ICE area, and take my foot off again, the engine will not shut down. This happens every time.

On the screen, the arrows point from the engine to the wheels and the engine to the Battery, and when the Battery gets to full, the engine will continue to run, but does not power the wheels or the Battery, an arrow goes from the battery to the wheels. When the battery drops again, the ICE will take over again.

Is this a recal event? I have read forum posts about this, but when I thought I've had a recal event before, they were much shorter than this, this is around a month now of this behaviour.

Can anyone shed some light on what may be the cause of this, please?

Maybe I'm reading into it too much, most people probably wouldn't notice.

 

Thanks.

[Mojo1010]

Weather is getting cold that is what. 

[CPN]

1 hour ago, Mojo1010 said:

Weather is getting cold that is what. 

What he said... and yes, it does make a huge difference to how our hybrids run (in the winter or cooler weather). Also, expect your fuel consumption to suffer by as much as 10% in the downward direction. (or upwards of you're looking at it from a fuel point of view) 

[Yaris2022]

Thanks both for your replies. I got the car at the start of this year, so I did experience some winter, but never noticed it doing that. Maybe I just wasn't 'used to it' at the time

But why would the ICE run even if it is up to temperature etc? The Battery used to hover around halfway, but now it seems to stay nearly fully charged all of the time. Is this a usual hybrid 'quirk'?

Thanks

[CPN]

These may seem stupid questions but you haven't been accidentally driving in "B" by any chance at any time? How do you have your climate control set on a normal drive? In other words, is there any way that you can think of that your normal driving would invoke such behaviour?

Are you keeping track of your neck to neck fuel consumption rather than relying on the dashboard indications? Do you have an Android phone? If so, I would highly recommend using Hybrid Assistant to get to the bottom of situations like this...

[Yaris2022]

No, I always make sure I drive in D, and normally, I have the climate control off in the car. I have tried both off and on, and it doesn't appear to make any difference, strange. I like to think I drive it to the best economy, so I can't think of anything that I've changed to cause this? Have you ever experienced anything of this nature?

 

Yes, I monitor the fuel consumption independently of the dashboard... the indicators seem to give best case scenarios. However, I have noticed, I used to get around 85MPG for my trips according to the dash... but since the ICE has been running more, it has reduced to about 45 - 50MPG. I do have an Android phone, yes.

 

Oh, and sometimes, halfway through a drive, it will go back to normal, with the 'rough' ICE shutdown when pulling off the accelerator, and will continue to do that. But most of the time, it runs the ICE. That I can't understand?

 

Thanks

[W1P30UT]

If you put the climate control into Eco mode it will prioritise fuel efficiency over cabin comfort, and this will reduce the engine running. 

[Cyker]

If mine is anything to go by it's totally normal - If you turn off the HVAC (Off button under the right-hand Auto knob) you'll probably find the car returns to its 'normal' behaviour.

The problem is heat, or lack thereof: The engine is very very efficient, but the downside of that is it doesn't get very hot during urban driving, and if you have the temp set to e.g. 20+C, it will quickly suck all the heat out of the engine to heat the cabin, forcing the engine to run to generate more heat.

It will try and use that to drive the car and charge the Battery so it doesn't waste the power, but when the Battery starts to fill up, the car is forced to switch to EV power to stop the Battery getting over-charged, and the engine will just waste energy still trying to generate heat for the cabin.

It definitely could have done with having a reverseable AC system so it could act as a heat pump heater, as heating is the only glaring source of inefficiency in the car! In summer I run with the AC on all the time and it doesn't impact the efficiency that much, but to get heating in winter you get a huge mpg hit - It's kinda weird as it's the total opposite of a normal car, which are normally toasty in winter but take a big fuel hit in summer with the AC!  

 

[Yaris2022]

I too agree that the heating system is quite wasteful when it comes to the hybrids... I tried using no climate control at all on my journeys today, by turning the fan right down, temperature right down, and pressing the 'OFF' button on the panel. This did not change the behaviour of the car, the engine was still running either powering the wheels / Battery or idling. Is this the correct method to fully switch off the heat?

The interesting part, however, nearing the end of my last journey, it did go into EV after I released the pedal, the EV light came on. So, I drove it for a bit longer, as I was nearly home, and it was acting normally, and even when the ICE kicked in, when I released the pedal, it would shut off again and the EV light would illuminate, these were roads with 30MPH limit and the Battery drained to around halfway during this 'test'.

However, when I accelerated onto a dual carriageway, it would not go back into EV upon releasing the pedal, and the engine ran, charging the Battery even through the slower 30MPH zone, until it was 2 bars from full, which then the EV light came on and the ICE shut off once again, without any intervention.

It seems strange that after periods of acceleration using the ICE, it will continue to run, either charging the battery or idling.

 

[CPN]

9 hours ago, Yaris2022 said:

Have you ever experienced anything of this nature?

Only on long cold trips in the winter time...

9 hours ago, Yaris2022 said:

Yes, I monitor the fuel consumption independently of the dashboard... the indicators seem to give best case scenarios. However, I have noticed, I used to get around 85MPG for my trips according to the dash... but since the ICE has been running more, it has reduced to about 45 - 50MPG. I do have an Android phone, yes.

Then again, I would thoroughly recommend Hybrid Assistant and an OBDII dongle (a good one not the cheap ones on eBay - if you can afford it of course). You will be amazed at the insight and education that it will give you into your hybrids' behaviour. I never drive without it running.

9 hours ago, Yaris2022 said:

Oh, and sometimes, halfway through a drive, it will go back to normal, with the 'rough' ICE shutdown when pulling off the accelerator, and will continue to do that. But most of the time, it runs the ICE. That I can't understand?

It sounds like "the brain" is hesitating over its "decisions" as to how to be powering the car...

[CPN]

@Cyker Perfectly explained! 😁

[CPN]

39 minutes ago, Yaris2022 said:

I too agree that the heating system is quite wasteful when it comes to the hybrids... I tried using no climate control at all on my journeys today, by turning the fan right down, temperature right down, and pressing the 'OFF' button on the panel. This did not change the behaviour of the car, the engine was still running either powering the wheels / battery or idling. Is this the correct method to fully switch off the heat?

If you need to, yes (but I have never felt the need to do this in ours...)

39 minutes ago, Yaris2022 said:

The interesting part, however, nearing the end of my last journey, it did go into EV after I released the pedal, the EV light came on. So, I drove it for a bit longer, as I was nearly home, and it was acting normally, and even when the ICE kicked in, when I released the pedal, it would shut off again and the EV light would illuminate, these were roads with 30MPH limit and the battery drained to around halfway during this 'test'.

This is normal behaviour for that kind of driving. Be aware that the Mk4 takes its L-Ion traction Battery down to much lower levels than the Mk3 used to do and can go as low as 25% SoC before it feels the need to bring the ICE in. (I see this daily just now using HA in this weather...)

39 minutes ago, Yaris2022 said:

However, when I accelerated onto a dual carriageway, it would not go back into EV upon releasing the pedal, and the engine ran, charging the battery even through the slower 30MPH zone, until it was 2 bars from full, which then the EV light came on and the ICE shut off once again, without any intervention.

The frequency of ICE use is MUCH higher in the winter than in the summer and this is normal.

39 minutes ago, Yaris2022 said:

It seems strange that after periods of acceleration using the ICE, it will continue to run, either charging the battery or idling.

There are four distinct stages that the Hybrid's electronics uses during system active. S1, S2, S3 & S4 and another which is labelled "idle check" which happens in stages S2 & S3 if it feels that it is needed. S1 is first start up with a cold engine and when it will try and use the traction Battery as much as possible whilst the ICE warms up. This seems counterintuitive to me as an offload ICE will take longer to warm up!

You can see all this happen in real time using HA. I nicknamed S4 as "Super Milk Float" mode because it doesn't come up very often and usually when everything is 100% perfect for the Hybrid to be running at its most efficient. When it gets to this mode (usually on a motorway on a long run), it is quite possible to see the EV light come up on a Mk4 at speeds above 60 mph but usually not for very long.... This never happened in the earlier Mk3 at those speeds. They tweaked the brain for the Mk4. Better ICE & better Battery allowed this.

[Cyker]

1 hour ago, Yaris2022 said:

I too agree that the heating system is quite wasteful when it comes to the hybrids... I tried using no climate control at all on my journeys today, by turning the fan right down, temperature right down, and pressing the 'OFF' button on the panel. This did not change the behaviour of the car, the engine was still running either powering the wheels / battery or idling. Is this the correct method to fully switch off the heat?

The interesting part, however, nearing the end of my last journey, it did go into EV after I released the pedal, the EV light came on. So, I drove it for a bit longer, as I was nearly home, and it was acting normally, and even when the ICE kicked in, when I released the pedal, it would shut off again and the EV light would illuminate, these were roads with 30MPH limit and the battery drained to around halfway during this 'test'.

However, when I accelerated onto a dual carriageway, it would not go back into EV upon releasing the pedal, and the engine ran, charging the battery even through the slower 30MPH zone, until it was 2 bars from full, which then the EV light came on and the ICE shut off once again, without any intervention.

It seems strange that after periods of acceleration using the ICE, it will continue to run, either charging the battery or idling.

 

It's not just an issue with hybrids, but any car with high thermal efficiency - My Mk1 D4D was the same! I'd be freezing my proverbials off in winter because it took so long for the engine to warm up. I could get half-way to work before the Cold Engine light went off on the dash on a properly cold day!

The difference there was the engine was always running, so once it warmed up it stayed warm, but with the hybrids, because they turn off to save fuel and use the electric motor, they cool down *very* quickly when the heater is sucking heat out of them (It's a small aluminium engine so can't retain as much heat as a big steel block!).

I tended to take longer faster roads to get home in winter with the D4D, and now the hybrid, just because it lets the engine run more without sacrificing efficiency as much as slow urban traffic does!

I do wonder how much it would cost to retrofit a heated steering wheel and seats like the euro-spec Yaris Mk4s have, as that would help immensely!

 

[Yaris2022]

Thanks again for the detailed replies - I didn't realise that so many people shared the passion for Toyota hybrid cars!🙂

I would like to put this down to the winter weather etc, and that does seem like a probable cause, but it started sometime at the end of August, which was still reasonably warm, if memory serves?

It then went back to "normal-ish" for a week, where the EV light would illuminate upon releasing the pedal etc, but then after would sometimes run the engine.

Then, the behaviour that I described above started, ICE not shutting down often if at all, which has continued.

The traction Battery always hovered around 50% SoC (1 bar above and below), but now seems to stay rather full, as the ICE is running to charge it.

I have heard about the warm-up stages, I believe I read about them on a Prius forum, so either the car is not going into S4 when it should, or something else is happening.

I originally thought this was a Battery recalibration, but I'm now somewhat doubtful that this is the case. It wouldn't bother me too much on dual carriageways etc, but when the ICE is running on 30MPH residential streets, where I would normally use electric... it's slightly irritating.

 

Oh, and if I press the EV mode button when driving below 30MPH and the ICE is running, the ICE instantly shuts down and the EV indicator lights, even when I'm accelerating. So clearly the ICE does not need to run, otherwise it would say that EV mode is unavailable, right?

 

According to the MyT app for January and February, the car was behaving normally, and not like it is currently, as there was lots of blue EV lines on my route. Most of my route is now grey lines for NON-EV.

 

[Cyker]

I'm fairly certain it's the temps as I've resorted to turning off the heating, esp. in the morning, in order to stop the car running the engine all the time; Had to do the same thing last year too!

You can try the same thing and see if you get similar results, but wear a warm coat, and maybe some gloves if you do try!!  

(That one good thing about the fake 'vegan' leather is it doesn't feel as cold as the steering wheel in my old Yaris!  )

 

[Max_Headroom]

I get that hybrid owners like all car owners want to get the maximum MPG,  i would rather lose 10% of my MPG than be cold in the car.

[Cyker]

Yeah I must admit it's not something I'd normally be bothered with but when you're normally getting 70-80mpg then see it dropping to the 60s... I just can't let it drop so low!!

Which is funny since the previous car (1.33 Mk2) could barely get past the 40's and the car before that (Diesel Mk1) 60's was normal!  

The annoying thing is that the car doesn't even get that warm if you're driving in urban crawl, so you're loosing nearly 20mpg to be in a lukewarm car. I suspect it'd be more efficient to pick up 3 people  (Or 4 small people) from a bus stop and drive them to their destination to warm the car up!  

[Max_Headroom]

13 minutes ago, Cyker said:

Yeah I must admit it's not something I'd normally be bothered with but when you're normally getting 70-80mpg then see it dropping to the 60s... I just can't let it drop so low!!

I get that but i would be happy with 60+ mpg for a few months  😉

[TonyHSD]

I would like to take Toyota hybrid to Oimyakon, the coldest town on earth ❄️ It would be fun to see if the car will ever turn off its ice , perhaps not as may not be able to start at all afterwards.  

[Max_Headroom]

26 minutes ago, TonyHSD said:

I would like to take Toyota hybrid to Oimyakon, the coldest town on earth ❄️ It would be fun to see if the car will ever turn off its ice , perhaps not as may not be able to start at all afterwards.  

Have a run to Scotland in winter that'll put it to the test  😉

[MikeSh]

2 hours ago, Cyker said:

I'm fairly certain it's the temps as I've resorted to turning off the heating, esp. in the morning, in order to stop the car running the engine all the time

14 hours ago, Yaris2022 said:

I have the climate control off in the car. I have tried both off and on, and it doesn't appear to make any difference

Why are people still saying it's having the cc on? It still 'misbehaves' when it's off. 

[Cyker]

Ha, I read that as cruise control and was confused  

Well in my experience, having the HVAC/climate control absolutely does affect how much the engine runs in winter, but YMMV as they say.

My one definitely behaves more like it does in warmer parts of the year with it off or the temperature set lower, but obviously there are other factors that can affect it, as even with the HVAC not taking heat from the engine, if it's cold enough outside the engine will still run more to keep itself at minimum operating temperature.

If my engine is running for no apparent reason, esp. if it's doing the thing where the engine is clearly running but the power meter shows it isn't supplying energy to the wheels or the Battery, hitting the off button on the HVAC will cause it to instantly shut off, so that's pretty hard evidence it has an effect.

 

That said, I think there may be more than one thing in effect here - I have noticed sometimes the engine will still run at maybe 800-1000rpm for no apparent reason, usually after I've been hooning it about; It's been suggested this may be the engine regenerating the particulate filter. However, this isn't season dependent as it happens summer or winter, so maybe the cold weather is a red herring in this case if that's all it is.

There are two distinct behaviours I've noticed - If it's 800-1000rpm it's this suspected-GPF-regen behaviour, but if it's over 1000rpm it's more likely heating.

I'm not sure how you'd tell without a HUD tho' as the non-HUD cars don't seem to have a way to display RPM?

 

The other difference is the maybe-regenning behaviour has basically no effect on mpg, but the heating behaviour has a substantial effect.

 

[MikeSh]

1 hour ago, Cyker said:

Well in my experience, having the HVAC/climate control absolutely does affect how much the engine runs in winter, but YMMV as they say.

I don't know how hard this can be.

The OP has said that even with the heating/climate control off the engine continues to run.

Just to repeat ... The OP has said that even with the heating/climate control off the engine continues to run.

So why are you and others continuing to say "Oh, it's the heating"?

Read the fricking information provided rather than using your preconceptions to diagnose things.

[Ralph H]

I think there could be a fault. 

Drove my car (for the first time in 2 days) 20 miles this morning outside temp 8 degrees had climate control set to 22 degrees with aircon on engine ran for 3 miles then went into ev mode at about 60mph on the motorway. Then operated normally for the rest of the trip. 

It showed 72mpg on the computer at the end of the trip. 
 

I think a trip to the dealer might be required. 

[Trewithy]

On 10/9/2022 at 12:02 PM, W1P30UT said:

If you put the climate control into Eco mode it will prioritise fuel efficiency over cabin comfort, and this will reduce the engine running. 

I put the CC into Eco mode today and the first thing I noticed was the reduced fan speed.  Then I was aware that the ICE was cutting out more frequently and the car was going further in EV mode.  Bound to be more economical so I will leave CC in Auto with Eco mode turned on.