I had driven a 2018 PHEV - GT from 2018 to late 2021, and was always able to remain in EV Mode by pressing the EV Button, foot on the brake and then Start Button. I would remain in EV , as AndyofOz mentioned, until the Drive Battery got low, or I Increased my speed or if the Ambient Temperature dropped to below -10C or if I turned on Cabin heating above 18 or 19C' on colder days. I never, ever received a message to "add fuel to use up old fuel" I loved my 2018 PHEV but the 12kWhr was a bit small.
Then on Sept 2021 I upgraded to a 2022 PHEV - GT. This car had a 13.8kWhr and worked pretty much the same as the 2018 except the the ICE would kick in sooner when Temps were not as cold, many times when the outside Ambient Temp was 7'C and interior heat set to 18'C. When this happened and when safe to do so I stop the car. Press the EV Button, then press the brake pedal and start vehicle, and car could remain in EV mode for the rest my trip or untill the Battery started to deplete or I required higher speeds, everything I had control of.
Also I could set the interior temp to 18C' and the ICE would not pick up unless I increased to 21 or 22C' and I was able to continue driving in EV Mode untill as previously mentioned, I increased my speed or the Drive Battery was low.
I usually drive in B0 mode and most of my driving is in the city and on both the 2018 and 2022 I could Regen by pedaling to B3, B4, or B5 with no problems. More on this a bit later.
Then in Apr 2024 I upgraded to a 2024 PHEV - GT 20kWh. It is a beautiful car but performed totally differently from the 2018 and 2022.
1st I noticed that as soon as I turned on the Interior Heater, even to 17.5C' the ICE turned on. I had to turn off car and restart. Then 5 or 6 minutes into my journey, the ICE turned on again, for no reason at all. I had a full battery and was only driving at 60kph.
As I mentioned before I usually drive in B0 mode, so I was very surprised to see that when I pedalled down to B3 or B4 or B5, the ICE started up. This never happened on my previous Models
I had to turn off the car. Pressed EV Button and with foot pressing brake pedal and pushing start, I was back in EV mode. But again, when slowing down and pedaling down to use Reggen, as soon as I got to B3 the ICE started again. (I was not impressed).
After posing this question to this forum I was told and correctly, that only when Drive Battery was below 55% full would the car remain in EV mode when reggen pedal was placed in B3 or higher.
During the summer I found the car to remain in EV mode, untill I turned on the AC but could not go back to EV Mode merely by turning off the AC. I had to turn off car to get back to EV Mode.
Then a few times, out of the blue, the ICE would start up, even though my speed was around 60 km/h, had the HVAC off and plenty of Battery Power left.
Then, after driving about 3 months, the ICE started up and I got message that I had to use up the old fuel and the ICE would not turn off untill I added 20 Lt of fuel. This never, ever happened on my 2018 and 2022 Models.
Again from this Forum I learned that everyone with 2023 and 2024 PHEVs is getting this message and the EV only Mode is not available until the message goes away.. by add at least 20 Lt of fuel (to satisfy the parameter)
Not sure where you live but I fear that when Temperature start to drop to below 0'C, the ICE will come on more often than needed even with plenty of Battery Power remaing
I will then try the procedure to force car into EV Mode.
Namely:
1) Press Start Button, without pressing brake pedal.
2) Press EV Button then
3) Press Brake Pedal and Start Buthon together.
Then see what happens
My biggest fear is when the Outdoor Temp drops to below -30C' because the Heat Pump will not work when Temps drop to below -20'C, so no pre-heating with Battery and from what I am reading, Car may not even be able to be started once the Main Battery Temp drops to below -25'C, whether car is plugged or charging at home or not.
On both my previous 2018 and 2022 I was able leave the fully charged car, UNPLUGGED in tempuratures that drop down to below-30C' while I was away vacationing in Mexico and when I returned the Main Battery usually dropped to 75% because the Main Battery Internal Heater was able to keep the Battery warmed up. And I was always able to start my car without plugging in.
Since the 2023, 2024 and 2025 PHEVs have no Main Battery Heater. I fear that many owners living in the Northern States and Canada, where we do get temperatures below -30C' may experience Starting problems, regardless of the car being plugged or not and may not even accept a charge once the Battery Temerature reaches -25'C.
Mitsubishi Motors really blew it with the 2023 and newer Models and I hope that they can admit their mistake and add a Heater to the Main Battery and allow us to at least allow us to use the Remote Control to start the ICE. Currently that is not an option.
Winter is only 2 months away. And with a forecasted la Niña approaching.
"Baby it will be cold outside" ☆☆☆☆☆☆ (Musical notes)