Premium unleaded in a PHEV

[Tucky]

Hi guys, picking up my brand new HS PHEV tomorrow. Very excited. On a daily basis I will be pretty much exclusively electric and the petrol engine will probably only get used sporadically. Would it be beneficial to use premium unleaded with its higher octane levels and cleaning additives, with regards to potentially aging petrol?

 

[salty]

Congrats on your new motor. Enjoy!

 

[BoJoUK]

Hi guys, picking up my brand new HS PHEV tomorrow. Very excited. On a daily basis I will be pretty much exclusively electric and the petrol engine will probably only get used sporadically. Would it be beneficial to use premium unleaded with it's higher octane levels and cleaning additives with regards to potentially aging petrol?

Absolutely. I have had my HS PHEV for just over a year (54 weeks) and I have just had its first service. I have done just over 6000 miles and have only ever put petrol into it 3 times. I still have 72% of its 3rd tank left, so have only used two and a quarter tanks of petrol, all because virtually all of my journeys are within its approx 75 mile EV range.
Just before I bought it I was recommended to only put in premium petrol and I have only bought it from a petrol station and never from a supermarket fuel station.
I am still delighted with the car and I am sure that you will be too. I think your thoughts on using premium fuel are absolutely right.

 

[Tucky]

Thanks . Really appreciate the advice. Premium it is!

 

[BarrieG]

The other issue not mentioned above is that Ethanol absorbs water. E10 petrol contains more Ethanol and is prone to absorb more water than E5 petrol. If you are doing a low mileage with the ICE it is recommended to use E5.
Even though we have a water scrubber fitted to our boat's outboard engine fuel supply, we always put E5 into our tank as it can often sit for long periods unused.
The additional cost is minimal when only a small quantity is being purchased.