Can I Choose Which Power Supply To Use?

Biker67

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HS PHEV
Hi Folks,

I think that I probably already know the answer to this question? But hopefully I'm wrong...

I see that it's possible to select EV only. But why can't I select petrol only? 🤔

From what I've read on the web. It isn't ideal to leave the high voltage battery either 100% full or 0% flat.
And seemingly the only way to run the petrol engine all the time is to flatten the high voltage battery?

Part of the deal with my recent purchase of the HS PHEV included a full tank of fuel. Plus I asked for E5 (super unleaded) As I'm aware that E10 (regular unleaded) doesn't store well long term. Especially in plastic motorcycle tanks.
Consequently, I'd like to run the petrol engine from time to time. Which will also keep it from developing potential issues from lack of use.
 
Extremely low Giller.
The SUV I PX'd had only covered 6400 miles from new in 6.5yrs.
I own other vehicles & the MG HS is just a fairly extravagant & comfy cruiser.
 
@Biker67 - Yes it's very easy to force the petrol engine to 'come to life'. Just put your foot to the floor of the accelerator at some traffic lights (or if you prefer, floor it whilst doing 10mph in a straight line). The petrol engine will (almost instantly) kick-in. It will then continue to run for at least a few minutes (unless you start driving very sedately, or come to a complete stop, at which point it will switch back to EV).

Basically, just enjoy the 300bhp for a few minutes, as you waft along some (hopefully) empty/fast roads.
 
Cheers @HStrophyPHEV2025rc but I was hoping there'd be a more subtle option mate? 🤣

The shove provided by the 300bhp is very impressive though!
I wouldn't say it's fast in the true sense of the word. But 6.8 secs to 62mph for a big lardy SUV costing under £40k is seriously impressive! 👍
 
@Biker67 You can change the default engine mode from EV to HEV by using the Infortainment. Then (if you like) you can program one of your star keys to toggle between EV and HEV as you drive.
However, to be honest, even if you change to HEV mode, if you drive like Mother Teresa you'll still not trigger the petrol to kick in (unless you have 0 miles range left in EV)
=> If you want to force the car to make the petrol engine start, then using a heavy right foot is the way to go.
 
I have my right hand star button set up to switch between the driving modes. And the left hand star button set to toggle between the brake regeneration options.
I reckon the higher brake regeneration mode will save a fortune in brake discs/pads.
I lift off the throttle & it feels like I've left the handbrake on! 😳
I like the idea that it gives more electric range. But it'll take a while to get used to the fact that I can lift off the throttle much later. And still not need to apply the brakes!
 
The high-voltage battery never runs completely flat. When the display shows 0 km and the petrol engine kicks in, the battery still has around 15% SOC. Just drive in HEV mode; the petrol engine will kick in from time to time and try to keep the high-voltage battery at around 50%.

However, the performance is only really good in Sport mode and when the battery still has enough charge left. I did find myself in a few tricky situations at first, driving in EV mode only and then trying to overtake – that wasn’t very wise of me. It doesn’t have full power straight away. The same thing happened on the motorway: battery flat, I kicked down the throttle and was a bit startled at how slowly it moved forward. I did drive the MG 4 with 200 hp for a short while in between; that was much more responsive.
 
Cheers @Totti1001
My plan is to use the high voltage motor as much as possible. But obviously I don't want the petrol to sit in the tank for years either.
From experience, I know that E5 is fine for 12-18 months. So if I use a tank of it per 12 months & EV mode the rest of the time. All should be well?
In fact, once I've used the tank of free fuel that came as part of the new car purchase deal. I'll probably only add 25% to the tank for emergencies.
 
Cheers @Totti1001
My plan is to use the high voltage motor as much as possible. But obviously I don't want the petrol to sit in the tank for years either.
From experience, I know that E5 is fine for 12-18 months. So if I use a tank of it per 12 months & EV mode the rest of the time. All should be well?
In fact, once I've used the tank of free fuel that came as part of the new car purchase deal. I'll probably only add 25% to the tank for emergencies.
Sounds like a plan, alternatively siphon it out and sell it on Ebay :)
 
My 1990 Polo 86c has been sitting idle for seven years, and the tank is still half-full of E10. It still starts up and runs 😉. But you can tell it’s lacking a bit of power.
 
My 1990 Polo 86c has been sitting idle for seven years, and the tank is still half-full of E10. It still starts up and runs 😉. But you can tell it’s lacking a bit of power.
Mate, that fuel could potentially cause damage to the fuel system. Add a fuel stabiliser or Syphon it out & put it in your lawnmower.
 
These are still proper cars; they’re not as fussy as the ones we have today. You can’t get by without a laptop these days 😉. A screwdriver and a pair of pliers are enough for most repairs 😄.
But I did pour an additive into the tank a while back. My MG definitely won’t get that old.
 
These are still proper cars; they’re not as fussy as the ones we have today. You can’t get by without a laptop these days 😉. A screwdriver and a pair of pliers are enough for most repairs 😄.
But I did pour an additive into the tank a while back. My MG definitely won’t get that old.
Even if your Polo runs carbs not EFI?
I'm still amazed that 7yr old E10 isn't causing you problems mate? 🤔
Does the car live indoors (in a garage)?
Because that'll have help enormously.
 
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