PHEV ICE coming on a lot

[Nick72]

Perhaps this is temperature related (minus 7 to minus 1 past few days) but the ICE is coming on when I'm in EV mode literally every drive or after about 10 minutes. SOC good, never below 8 miles and we'll into the green on the gauge but usually nearly full. 

As I wait for the health centre to open for another COVID booster I'm in the car, it's in EV mode, air con on low. ICE has fired up twice now in the last 30 minutes (was hoping the centre was already open and I could get in sooner!). 

Now I know that the ICE is fired up occasionally to keep the engine lubricated but over the past few days it has come on every drive. I don't recall anything like this frequency last winter which makes me a little puzzled.

Temperature?

Note... Front demister, rear window heater, heated seats all OFF.

Hoping this is not related to my now supposedly fixed 12V issue in the other thread. Still starting fine but not been able to leave the car alone for more than 2 days. Out on business in it most of the coming week so it will be used every day including long motorway trips.

[philip42h]

9 minutes ago, Nick72 said:

Perhaps this is temperature related (minus 7 to minus 1 past few days)

I'd assume that it was temperature related and ignore it for now (until the spring) ... lest paranoia and insanity threaten ... 😄

[Hybrid21]

I would say definitely temperature related, the ICE firing up to supply heat inside the car.

[ernieb]

+1, temperature.

[Mojo1010]

Edit: Should be -7 like the post below 😄

+100 🤔

[philip42h]

At a guess, the ICE is being called upon to help out the heat pump ...

You'd be surprised and disappointed if the heat pump couldn't easily manage a 10 degree gradient - i.e. cool the car from 30 degrees outside to 20 degrees inside and/or heat the car from 10 degrees outside to 20 degrees inside. That should be easy.

But once you get to and beyond a 20 degree gradient things get a lot more difficult - the heat pump becomes less efficient and a proportionally far more work to do. So cooling the car from 40 degrees outside to 20 degrees inside and/or heating the car from 0 degrees outside to 20 degrees inside may be a problem without a bit of help from the engine.

What temperature was the climate control set to? Attempting to get from -7 degrees outside to, say, 22 degrees inside is likely more than the heat pump can achieve on its own.

[kucyk]

50 minutes ago, ernieb said:

+1, temperature.

-7 😏

[Hayzee]

I'd agree it being due to temperature. Also I've noticed that the ICE comes on whenever I activate the front screen demister (fan blowing max) regardless of outside temperature and stays on for a full warm up cycle.

[Strangely Brown]

I have noticed the same thing in my HEV. The ICE is in play a lot more for the same journeys and shows a corresponding drop in fuel economy.
Hey, it's winter. It gets cold. Batteries don't like cold and heat dissipates quickly.

¯\_(ツ)_/¯

[Nick72]

2 hours ago, philip42h said:

At a guess, the ICE is being called upon to help out the heat pump ...

You'd be surprised and disappointed if the heat pump couldn't easily manage a 10 degree gradient - i.e. cool the car from 30 degrees outside to 20 degrees inside and/or heat the car from 10 degrees outside to 20 degrees inside. That should be easy.

But once you get to and beyond a 20 degree gradient things get a lot more difficult - the heat pump becomes less efficient and a proportionally far more work to do. So cooling the car from 40 degrees outside to 20 degrees inside and/or heating the car from 0 degrees outside to 20 degrees inside may be a problem without a bit of help from the engine.

What temperature was the climate control set to? Attempting to get from -7 degrees outside to, say, 22 degrees inside is likely more than the heat pump can achieve on its own.

Sounds plausible. 20C

[TonyHSD]

Ice might be starting not only to provide heat to the cabin but also to prepare itself and be ready to take over when traction Battery goes low. Imagine driving at 60mph and engine start without been run at all for days and it’s negative temperatures outside. 

[ernieb]

At -10oC the heat pump more of less gives up so approaching that will likely fire the ICE.

[HSDish]

Noticed that in our PHEV to.

The latest days wed had from -9 (night) to -4 (day) and the ICE kicks in much more often even in EV mode. We have inside temp set to 22C and seat heat on full, occasionally steerwheel heat on

Also notised that the ICE kicks in even if its  3-9 km left of EV.

And... naturally we cant get that 50 km(winter, down to +-0 C) -75 km (summer) on one full charge that we use to

[nlee]

It says the ICE will start if the hybrid system is too hot or too cold.

 

[Nick72]

8 hours ago, Hayzee said:

I'd agree it being due to temperature. Also I've noticed that the ICE comes on whenever I activate the front screen demister (fan blowing max) regardless of outside temperature and stays on for a full warm up cycle.

Yes it does. It's more efficient to light up the engine from a thermal perspective.

[Nick72]

5 hours ago, TonyHSD said:

Ice might be starting not only to provide heat to the cabin but also to prepare itself and be ready to take over when traction battery goes low. Imagine driving at 60mph and engine start without been run at all for days and it’s negative temperatures outside. 

I have noticed that full power contribution from the ICE is not available until the engine has warmed up. Seems repeatable from my experience of flooring it. Not as much power in the first 5 or so minutes of ICE running. Assuming a protection feature.

Though I've just been pottering around at 20 to 30mph recently so nothing for the machine to think it needs to put the ICE on because of an off chance of doing 60mph.

[Nick72]

1 hour ago, nlee said:

It says the ICE will start if the hybrid system is too hot or too cold.

 

Must be temperature for sure in that case. 200 mile drive tomorrow and again the day after so will see what it does.

[TonyHSD]

8 minutes ago, Nick72 said:

I have noticed that full power contribution from the ICE is not available until the engine has warmed up. Seems repeatable from my experience of flooring it. Not as much power in the first 5 or so minutes of ICE running. Assuming a protection feature.

Though I've just been pottering around at 20 to 30mph recently so nothing for the machine to think it needs to put the ICE on because of an off chance of doing 60mph.

Even at low speeds the car will decide when it’s best to start the ice and pre condition it to be ready. Perhaps in summer when 20C° air temperature starting on the ice at 30mph after been off for long time it’s not a problem but at -4C° and below might not be as healthy for the engine. Also ten system may protect the Battery too , starts engine and take some load off the Battery until Battery reaches more ambient temperature. This is typical behaviour for all Toyota hybrids even non phev. 

[HSDish]

9 hours ago, philip42h said:

At a guess, the ICE is being called upon to help out the heat pump ...

You'd be surprised and disappointed if the heat pump couldn't easily manage a 10 degree gradient - i.e. cool the car from 30 degrees outside to 20 degrees inside and/or heat the car from 10 degrees outside to 20 degrees inside. That should be easy.

But once you get to and beyond a 20 degree gradient things get a lot more difficult - the heat pump becomes less efficient and a proportionally far more work to do. So cooling the car from 40 degrees outside to 20 degrees inside and/or heating the car from 0 degrees outside to 20 degrees inside may be a problem without a bit of help from the engine.

What temperature was the climate control set to? Attempting to get from -7 degrees outside to, say, 22 degrees inside is likely more than the heat pump can achieve on its own.

Thought abot this and its sounds right but,

As far as I could experience our car manage to pre heat the cabin and defrost windows even when its -4 C outside and our preset are 20 C inside if I start the preheat funktion with MyT app or the AC button on the key. IF the traction Battery are charged or the cord is connected to the socket/charge station

[Dippy]

A whole thread to discuss ICE appearing at low temperatures… the state of education these days…