Are any of you noticing a fuel economy impact running E10?

Soldato
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So by using that same logic would you see a 27% drop between running E5 and E85?

To run E85 you generally need to retune your car so it is hard to do like for like. People generally tune for power instead of economy. But yeh, 30% is about right.
 
Soldato
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The same, I drive with my MPG monitor always active and I always watch what I'm doing to avoid waste.
I have autism, and I'm weird with numbers.. I can literally see the difference in the MPG monitor running E10.



All urban, on both occasions, my car is only used to commute to work and back so my mileage each week remains the same. As I drive watching the MPG monitor and being very careful with my right foot. I know that a difference in driving style is not a possible reason for the difference I am seeing.



I did top up last night with £10 of E10 to an empty tank and noticed lower MPG this morning.. I know there's still some other fuel in the system but the majority is now E10.
When I said 'topped up with E10' what I should have said was car was ran till empty and I put a full tank of E10, as that's what happened with both of the FULL tanks I put in.


I'm working this out on the obvious differences I can see from the trip computer when either fuel is put in. On every tank I reset all trip computers IE average speed MPG and monitor what I achieve for the following month. This is how I know my differences are not due to driving style as that doesn't change.


I said it was an anecdotal experience and should be taken as such, that said, I have a predisposition to believe real world experience over lab results, given my complete understanding of how corrupt both humans and our energy industry is!



Well.. I don't really want to go into it too much, its all very personal you see! I'll just say I've had a much harder life than practically anyone I know, I've spent more Christmas' and Birthday's alone than anyone should, I have no reason to pick myself up each day but I do, and not only that, but in spite of everything and everyone I lost, I achieved my childhood dream of becoming a K1 world champion.

When I say you'd respect me, you would, because my presence would intimidate you as it does all others. (even fighters and sparring partners)

We aren't all built the same!

Have a great weekend <3

EDIT. For what it’s worth.

Both tanks of E10 got me 210 miles. Before the switch I was getting 280 miles per tank.

But sure, despite my experience with cars and driving, it’s probably just the weather!

You need to read what you write. Then seriously think if it comes across correctly.

What you wrote in your last paragraph would make me want to simply avoid you. Not out of fear or respect, simply due to your attitude.

Your ego is worse than an Irish fella who is into MMA...

You also don't use the trip computer to work out MPG.

It's a maths formula based on a full tank used.

My cars OBC is frequently 2-6mpg out either way.

Anyway, keep banging that drum..
 
Associate
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I'm definitely noticing it being used up much quicker, have a seat Toledo and a Skoda fabia, same engine definitely noticing both not go as far on a tank fill. Tempted to go for lpg on the next car I buy, thinking a duster at the mo
 
Soldato
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UK
Well, since the wife tested positive for Covid the day after starting this thread i've been doing literally all of the running around for the last week.

Wednesday morning came around & I managed to time it so i'd hit a shell station a few miles away from home with the car running on fumes so as an experiment I brimmed it with Shell Vpower whereas it's been filled with Shell E10 ever since they released it.

Going by the trip computer running a 3.6 mile portion of the same stretch of road from where I live to the nearest M1 junction on a pre-warmed engine with the cruise set at 50 i've got an increase in MPG displayed from 33.7MPG at 6.5c to 37.9MPG at 1.0c, it's only 1 run on each fuel of course but it's a dual clutch and given it was a clean run without having to brake or disengage cruise literally all I did was steer I can't see how there could have really been any other variables, it was a good bit colder too on the run with the higher figure.
 
Soldato
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3.6 mile portion?

You see there are loads of things that could severely affect such short journeys. How cold is the air temp? Cooler air temps are actually good for the car once warmed up. Even slight differences in traffic. Is your alternator working a bit harder from one run versus the other to top up the battery? How does your car react to 99 ron fuel?

My mpg doesn't stay the same from one 500 mile section to the next and can deviate by up to 10% even for the journeys made up of the same commute every day. I use odometer and fuel filled as the proper measure as the car computer is terrible at estimating mpg.

What people aren't doing are properly controlled large sample tests and that is why nothing I've seen is convincing.

Last car:
last.jpg


Current car:
current.jpg
 
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Soldato
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Glasgow
I almost always use Momentum 99 in my car, but Tesco didn't have any (on two separate days I visited) so I put in £20 of E10 last week, from empty.

Totally unscientific, but fuel economy appears to be a bit worse, performance and "smoothness" is worse and acceleration is quite sluggish and not far off how the car felt when I had issues with the turbo. This is in a 2014 Seat Leon FR 1.4 TSI so it's a modern enough engine.

Just to update on this, performance seems to have improved so either the car was "adjusting" to the different fuel or it was just having a bad few days. Still not quite on par with what I'd get from M99 but good enough. I'll still be sticking with M99 or similar though.
 
Soldato
Joined
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UK
3.6 mile portion?

You see there are loads of things that could severely affect such short journeys. How cold is the air temp? Cooler air temps are actually good for the car once warmed up. Even slight differences in traffic. Is your alternator working a bit harder from one run versus the other to top up the battery? How does your car react to 99 ron fuel?

My mpg doesn't stay the same from one 500 mile section to the next and can deviate by up to 10% even for the journeys made up of the same commute every day. I use odometer and fuel filled as the proper measure as the car computer is terrible at estimating mpg.

What people aren't doing are properly controlled large sample tests and that is why nothing I've seen is convincing.

Last car:
last.jpg


Current car:
current.jpg

Yep, 3.6 miles as it's a reliable 3.6 mile stretch of road where I know that I have to do nothing but steer which takes out variables like accelerating, braking & gear shifts, you just sit at a solid 50mph all slightly uphill.

It's a 50 limit with 3 cameras along it and is a fairly quiet stretch with little traffic interference unless you catch a HGV or Tractor.

I'm not going to repeat it on purpose of course but every time I traverse that stretch I might reset the trip and record mpg, and temperature out of interest.

And I know that the trip is terrible & tends to be optimistic but i'm looking at the variation rather than the outright figure.
 
Soldato
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I only use E5. Probably won’t be long until they dilute that even more.
Worth noting that while Super is marked as E5 on the pump it's only an "up to", a number of brands (I.E ESSO) have Ethanol free Super so the MPG advantage over E10 will be even more pronounced.
 
Man of Honour
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Worth noting that while Super is marked as E5 on the pump it's only an "up to", a number of brands (I.E ESSO) have Ethanol free Super so the MPG advantage over E10 will be even more pronounced.

That is indeed interesting. Any other brands with ethanol free super?
 
Soldato
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Bryn Celyn Wales
100% getting way lower, I've had to take the hit and be running E10 in my Xedos and it's dropped massivly in general everyday driving... so I don't care what the "authorities say", you get less energy per bang and thus you get less mpg, simple as that and my Xedos is down around 20+ percent easily
 
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