E10 petrol degradation over time.

[Pat_D]

I bought my NX450h+ because the electric range almost exactly matches the longest daily journey I routinely make. I took delivery of the car just over 3 months ago, with a full tank. It’s still got that same full tank. We are told that E10 degrades over time, and the advice varies but it would appear that it should be used within 3-6 months. Some suggest that replenishing one third of the tank effectively “refreshes” it. Anyone got any experiences/advice in this area?

Cheers

[Bounce75]

I deal with a few lawnmowers that use E10 petrol & I can tell you it definitely goes off. You can use a fuel additive to preserve it or use E5 petrol if you are going to leave it in the tank for a while.

[Bluemarlin]

15 minutes ago, Pat_D said:

I bought my NX450h+ because the electric range almost exactly matches the longest daily journey I routinely make. I took delivery of the car just over 3 months ago, with a full tank. It’s still got that same full tank. We are told that E10 degrades over time, and the advice varies but it would appear that it should be used within 3-6 months. Some suggest that replenishing one third of the tank effectively “refreshes” it. Anyone got any experiences/advice in this area?

Cheers

As I understand it it's the ethanol that significantly reduces shelf life. That being the case, if I hardly used any petrol, I'd use Esso E5, which is zero ethanol.

In the meantime there are fuel stabilisers you can add that will extend the life of E10 up to a couple of years.

[Spock66]

So logic would be if it's the Ethanol that degrades then E5 would also be impacted, but maybe effects are less noticeable.

[Bluemarlin]

10 minutes ago, Spock66 said:

So logic would be if it's the Ethanol that degrades then E5 would also be impacted, but maybe effects are less noticeable.

As  I understannd it E5 is less affected, but the whole thing can be avoided by using ethanol free petrol, like Esso E5.

[rayaans]

All fuel goes off so to speak. But it does tend to go off on E10 a lot quicker

Ive noticed how quickly it goes off in our ride on definitely much more than I used to with e5

[wharfhouse]

1 hour ago, Bluemarlin said:

As  I understannd it E5 is less affected, but the whole thing can be avoided by using ethanol free petrol, like Esso E5.

Note on the Esso website:

We currently supply an ethanol-free Synergy Supreme⁺ 99 unleaded in some parts of the UK. From September 2023 our Synergy Supreme⁺ 99 will transition to contain up to a maximum of 5% ethanol at all Esso pumps irrespective of which part of the country they are located. The labelling at our pumps will remain as E5 for Synergy Supreme⁺ 99 unleaded.

[wharfhouse]

52 minutes ago, rayaans said:

All fuel goes off so to speak. But it does tend to go off on E10 a lot quicker

Ive noticed how quickly it goes off in our ride on definitely much more than I used to with e5

I switched to E5 some time ago on my IS 300h. Simple supermarket brand E5 gives measurable better mpg than any E10 (supermarket or any of the branded). At least 5% and up to 10% improvement, which I know is a lot more than should be the difference, but found this reliably over many tankfuls comparing E5 and E10. So, as long as the price difference between E5 and E10 is less than 10% I generally save money using E5 (supermarket E5 is less than 10% more expensive than E10, but branded fuel is probably not). I also noticed that E10 mpg gets noticeably worse as the fuel ages in the car (even over a few weeks) whereas the E5 mpg does not degrade when left the same time in the car.

[Scotlex]

You should try to use E5 petrol if possible (super unleaded) and also try to refill the tank every 6 months approximately.

If you continue to not use any petrol you should look at a full electric model.

[Mr Vlad]

Pat. Use your car much more often. Try to 'burn' half a tank of fuel. Go for a 200 odd mile drive. 

You bought a hybrid for economy reasons. Sorry but the mileage you do you should have bought an electric car.

You most certainly are not doing that car of yours any favours.

[NiCoRe]

What you can do is use charge mode from time to time for a few miles and top of your tank every time you have a chance to do so. 
 

[Harrier Man]

My situation was very similar Pat, my local commute can be achieved using Battery alone. However, once a week the car gets a 120 mile blast, which it needs, especially in winter. Even so, I was getting some sludge build up in the oil (hence, please do change the oil even if the engine miles are low).

For my very long trips to visit family, I am happy to put in the cheaper E10 fuel as I know that I'll burn through the tank before the fuel degrades noticeably. When I know that I have no long trips planned, and as I go into winter, I will fill up with E5 because there is a greater chance of the higher methanol content of E10 absorbing condensation and the petrol degrading and possibly leading to corrosion in some parts of the fuel system. A small risk maybe but one that I will reduce by using E5. 

Supermarket E5 appears to be a good compromise. As Phil mentions, the price difference is not as large as it is at the independents and now that Esso is changing its E5 from zero ethanol (in some parts of the country) to 5% everywhere from September, I reckon that E5 will be a very similar quality wherever you buy it. With the added bonus of a couple more mpg.

[Hookyman]

I believe the fuel tank on the hybrid models are pressurised, which in some way extends the shelf life of petrol. 

[Alan Thompson]

Before the Lexus 450h+ I had a Mitsubishi Outlander PHEV and that would force the engine to run after a number of weeks and would keep running it every journey until 15 litres of new fuel was added.

I am like you Pat, most of my journeys are within the electric range. What I tend to do is force the engine to start once a week when I have a 7 or 8 mile each way motorway journey. This allows me the option to fill up more regularly, although I tend to only fill up when I've got a long journey ahead (every 3 months or so).

[Pat_D]

Thanks to all for your replies, particularly Malcolm, Gary and Alan. I now have the car running in HV mode, and expect to refill (with E5) very shortly.

To those who told me I needed a full EV, discard any sharp objects around you, and urgently seek counselling. 😀 EV is not yet the way forward.

Pat

 

[Redefined]

Don't know much about degradation, but my commutes are about 100 miles each way on average - at least twice per week. Sometimes a bit more than that.

On the ls430 my experimentation has found that the mpg on the 99ron fuel is alot better than the 95ron (E10). But also find different petrol stations are slightly different in quality (I believe and read somewhere that some places are not as honest with only filling their higher ron tanks with the more expensive stuff.

Anyway, so the best I've found is Shell vPower. Gives me 35mpg on a run (200 miles one way) and on a couple of occassions I've managed to get upto 38mpg (driving very smoothly due to being short on cash/fuel and needing to extend the range!

Have tried the same thing with the E10/95ron but no way could I even get to the 33mpg mark (long run of 100+ miles, driving at close to 56mph and smooth as poss). Sorry for going off topic!

[wharfhouse]

1 hour ago, Redefined said:

Don't know much about degradation, but my commutes are about 100 miles each way on average - at least twice per week. Sometimes a bit more than that.

On the ls430 my experimentation has found that the mpg on the 99ron fuel is alot better than the 95ron (E10). But also find different petrol stations are slightly different in quality (I believe and read somewhere that some places are not as honest with only filling their higher ron tanks with the more expensive stuff.

Anyway, so the best I've found is Shell vPower. Gives me 35mpg on a run (200 miles one way) and on a couple of occassions I've managed to get upto 38mpg (driving very smoothly due to being short on cash/fuel and needing to extend the range!

Have tried the same thing with the E10/95ron but no way could I even get to the 33mpg mark (long run of 100+ miles, driving at close to 56mph and smooth as poss). Sorry for going off topic!

Similar to my experience between E5 and E10 - up to about 10% better mpg with E5 even though the chemistry says it shouldn't be that much...!  Maybe it's the additional higher RON that makes the additional difference. 

[Bluemarlin]

10 hours ago, wharfhouse said:

Similar to my experience between E5 and E10 - up to about 10% better mpg with E5 even though the chemistry says it shouldn't be that much...!  Maybe it's the additional higher RON that makes the additional difference. 

Could be. My experience is also similar. E10 will get me an average of around 27/29 in mixed driving, whereas my current average is 36 with E5. On a long run, if I stick to around 60-65mph I can get 40/41 mpg, which is pretty good for a big car.

[BonzoSPB]

12 hours ago, Redefined said:

Don't know much about degradation, but my commutes are about 100 miles each way on average - at least twice per week. Sometimes a bit more than that.

On the ls430 my experimentation has found that the mpg on the 99ron fuel is alot better than the 95ron (E10). But also find different petrol stations are slightly different in quality (I believe and read somewhere that some places are not as honest with only filling their higher ron tanks with the more expensive stuff.

Anyway, so the best I've found is Shell vPower. Gives me 35mpg on a run (200 miles one way) and on a couple of occassions I've managed to get upto 38mpg (driving very smoothly due to being short on cash/fuel and needing to extend the range!

Have tried the same thing with the E10/95ron but no way could I even get to the 33mpg mark (long run of 100+ miles, driving at close to 56mph and smooth as poss). Sorry for going off topic!

35mpg?

At the weekend I did a 200 mile motorway run at a steady 80mph and managed 45mpg over the entire trip in HV mode (starting off with hardly any electric).

Yesterday I did a 100+ mile trip starting off fully charged in HV mode and did 57mpg.

I'd be mortified at only getting 35mpg.

[Redefined]

Yes, sorry @BonzoSPB I'm from the polluting big barge V8 team (sorry Greta). So the car in question is the LS430. Spark plugs changed; lots of (well, almost half a bottle) Miller fuel additive added over the past 10,000 miles; tyres are winters so maybe I could up the pressure a touch; oil & filter renewed 5000 miles ago.

38 is probably the best I've gotten to but that figure the end average over 200 miles or so. Driving without annoying the lorries (so, just a bit faster). Aircon in the on position so I could keep the windows/roof closed to optimise laminar flow.

[BonzoSPB]

Ah, apologies @Redefined, I should look at the model being discussed in future 😁.

[Redefined]

Nope. My fault. The threaddid start discussing a hybrid. I just like to shout about my 35 - 38mpg whenever I get a chance. Such lovely cars these Lexi' (is that the plural).

[Mr Vlad]

16 hours ago, Pat_D said:

Thanks to all for your replies, particularly Malcolm, Gary and Alan. I now have the car running in HV mode, and expect to refill (with E5) very shortly.

To those who told me I needed a full EV, discard any sharp objects around you, and urgently seek counselling. 😀 EV is not yet the way forward.

Pat

 

LOL Pat. I most definitely do Not need counselling for suggesting you need an EV for the distances you travel. I'm a petrol head and Proud of it. I'm also a realist and know that EV's have their place Today. The fact is an EV is the vehicle I should be driving for the distances I do. I would too if I could afford it so I'll stick with my V6 and continue putting my 2 penneth in within the fabulous forum 😁

[Kaizen]

On 7/10/2023 at 9:06 PM, Pat_D said:

Thanks to all for your replies, particularly Malcolm, Gary and Alan. I now have the car running in HV mode, and expect to refill (with E5) very shortly.

To those who told me I needed a full EV, discard any sharp objects around you, and urgently seek counselling. 😀 EV is not yet the way forward.

Pat

 

Can't agree more regarding EV - 🙂

[WhiteHart]

Very good thread and very helpful. Thank you all for your input. Now also running down the tank..