Hi Billy there is a lot of information concerning the use of the phev in this forum and its a great way to find useful information ( by searching for topics).
I will try to quickly answer your questions but its not easy to do LOL
1) The main thing to start the ICE ( so you cannot use it in EV mode) is the heater, as the heat is obtained from the water flowing around the ICE ( as per normal ICE cars). If you select any temperature on the HVAC screen ( basically the screen to put the heater/blower on , or put AC on or the heated seats) then the ICE will start . E.G if you start the car , select 20c for the heater , the ICE will run and you will feel the heat blowing once the ICE has warmed up ( just like any other ICE car) , once its up to temperature then you can manually select EV mode , and if the heater is at the required temperature , it will switch to EV mode ( if its not then it will stay in ICE mode and you can try again later).
Once switched to EV mode, you can run in EV mode ( and it will still blow hot) until the heat in the engine cools down to below your selected temperature and so will start the ICE ( automatically) until it heats up again , and you can repeat the loop.
Its a case of trial and error , and although it may sound complicated/ messy , its not really and you soon get used to switching to EV mode manually using the EV switch ( well i have anyway).
Now on the HVAC screen selecting LO as the temperature will not start the ICE ( but it blows the outside air in)
Using the AC in summer does not cause the ICE to start
Using the heated seats also does not cause the ICE to start
2) Apart from no 1 above the other one to stop EV mode is if you go down a long steepish hill and use the regen / brakes to keep you speed down , when you get to the bottom of the hill you will find the ICE kicks in for a few mins ( the thinking is its to protect the regen motor from overheating ) , so again after a couple of mins try to manually select EV mode , and it will switch when the cars happy.
This has only happened to me on a steep hill which is about 1/3 of a mile long
3) On long journeys ( especially on the motorway) its best to leave it in the normal hybrid mode and let the car decide when to switch , so while driving it will automatically charge the battery ( a little) from excess power from the ICE ( like if your going down hill so coasting more)
I personally then manually use EV when driving through towns at either end of the motorway as its only under 24mph will it auto switch to EV mode.
MPG on long journeys depends on the length of the journey and we seem to gat about 40 MPG on ICE only , but its also only calculated on petrol used not electric, so as a rough example.
In the summer you can get up to 40 mile of EV use .
So any journey below 40 mile is great 999 MPG
So 60 mile shows 120 MPG ( 40 miles EV not shown in calculation, 1/2 a gallon for the last 20 miles , so 1/2 a gallon used for 60 miles , so 120 miles per gallon
If your journey is 80 miles it will show 80 MPG ( 40 miles EV not shown in calculation , so only using 1 gallon of petrol for the other 40 miles, so 1 gallon used 80 miles driven)
So the longer the journey, the less effective the EV range is in that total , so the greater petrol is used ( it is a big heavy brick shaped SUV after all LOL) so i have seen we tend to get about 40 MPG on longer journeys.
The rule of thumb is , don't get home with any battery left as you have not been the most efficient
So for me personally , most of my journeys are local and below 40 miles , so mostly on EV mode.
I can live with 40 MPG on the odd longer journeys i do ( for holidays etc) as i have no charger anxiety ( as we go to places that are very sparse on the charger front) and so i can easily fill up with petrol and be on my way again.
I hope that helps
sorry it wasn't quick after all lol
