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

Permabanned
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yet it turns out you were comparing 95RON E10 with premium 98RON E5

Wrong. I got 24 mpg from 95 RON before it was changed to E10, putting in E10 I got 18 MPG.
I then put in 98 RON as 95 RON in non E10 form is unavailable where I am - my fuel economy then returned to 24MPG.

For what its worth, my engine is designed for 95 RON - and it states on the petrol cap there are no benefits to running anything higher.

You see.. you shouldn't try and fill in the blanks, without understanding what the blanks are your mind will skew things in the way of your desired outcome.
It's actually a form of ignorance, which may explain why you are so quick to put down people giving their experience with this fuel?

Its either you're ignorant, or you're a shill for the EU commission!

Funny how a couple other TFSI owners on this thread have mentioned an MPG drop similar to what I experienced.

But hey... its probably just the weather!

RIGHT?

Derp.
 
Soldato
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Wrong. I got 24 mpg from 95 RON before it was changed to E10, putting in E10 I got 18 MPG.
I then put in 98 RON as 95 RON in non E10 form is unavailable where I am.

For what its worth, my engine is designed for 95 RON - and it states on the petrol cap there are no benefits to running anything higher.

You see.. you shouldn't try and fill in the blanks, without understanding what the blanks are your mind will skew things in the way of your desired outcome.
It's actually a form of ignorance, which may explain why you are so quick to put down people giving their experience with this fuel?

Its either your ignorant, or you're a shill for the EU commission!

Funny how a couple other TFSI owners on this thread have mentioned an MPG drop similar to what I experienced.

But hey... its probably just the weather!

RIGHT?

Derp.
Sorry dude but I’ve not got an apples to apples comparison but we haven’t noticed such a big drop that you have in ours. I use millers eco max on every other tank though not sure how that effects it.
 
Soldato
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Wrong. I got 24 mpg from 95 RON before it was changed to E10, putting in E10 I got 18 MPG.
I then put in 98 RON as 95 RON in non E10 form is unavailable where I am - my fuel economy then returned to 24MPG.

For what its worth, my engine is designed for 95 RON - and it states on the petrol cap there are no benefits to running anything higher.

You see.. you shouldn't try and fill in the blanks, without understanding what the blanks are your mind will skew things in the way of your desired outcome.
It's actually a form of ignorance, which may explain why you are so quick to put down people giving their experience with this fuel?

Its either you're ignorant, or you're a shill for the EU commission!

Funny how a couple other TFSI owners on this thread have mentioned an MPG drop similar to what I experienced.

But hey... its probably just the weather!

RIGHT?

Derp.
To be fair I wouldn't be calling people ignorant while claiming changing from E10 to E5 gives you a 1/3rd increase in your fuel economy :p
 
Man of Honour
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My this got angry quicker than normal.

Let's hope 2022 has less anger.

As you were boys n girls.
 
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.
 
Soldato
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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.
To be expected really going from 99ron down E10 which is probably the equivalent to 92/93ron. My polo is supposed to produce 192bhp but many claim it’s more like 200 when running 97ron.
 
Soldato
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5% less petrol 5% more ethanol. Probably not scientifically correct. What is the difference between 97ron and 95ron?

95RON being E10 or E5 doesn't mean it's not 95RON anymore. For a given RON figure, the ethanol content will primarily only alter the energy density of the fuel.

It can be used to alter the octane if specifically aiming to do that, but typically you'd expect more ethanol to mean a higher RON figure if anything (See for example E85 fuels, which are often something like 104RON or higher IIRC).

Whilst ethanol can be used to influence the octane rating, more ethanol doesn't mean 'equivalent to a lower RON'.
 
Soldato
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95RON being E10 or E5 doesn't mean it's not 95RON anymore. For a given RON figure, the ethanol content will primarily only alter the energy density of the fuel.

It can be used to alter the octane if specifically aiming to do that, but typically you'd expect more ethanol to mean a higher RON figure if anything (See for example E85 fuels, which are often something like 104RON or higher IIRC).

Whilst ethanol can be used to influence the octane rating, more ethanol doesn't mean 'equivalent to a lower RON'.
Ok so factually not correct but my point was, it is even further less energy dense than the Tesco 99 that he has always filled up with, therefore not surprising he is experiencing what he is.
 
Associate
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Bellinger service guy (seemed very knowledgeable) said my mpg drop isn't anything to worry about, but he would still put premium fuel in because it'll pay for itself in mpg and maintenance costs.
 
Associate
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I switched pretty quickly to vpower after running e10 for a few weeks, in a morning the engine would misfire or be very hesitant until it warmed up and from £20 of fuel there was very little difference in mileage so use vpower or the Tesco equivalent.
 
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I switched pretty quickly to vpower after running e10 for a few weeks, in a morning the engine would misfire or be very hesitant until it warmed up and from £20 of fuel there was very little difference in mileage so use vpower or the Tesco equivalent.

Either go get your car fixed / tune your carb or stop driving a race car on the road.
 
Associate
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Either go get your car fixed / tune your carb or stop driving a race car on the road.
There very well could be something amiss with the engine, why there has to be something wrong with it though when before e10 it was fine and on vpower or equivalent it's fine, like I said it was only on a cold start and once warm it's was ok.
it's a 1.6l focus so it's certainly doesn't get used like a race car nor did it bother me much but when pulling out of a junction and it doesn't want to go, I just changed to the vpower to see if the issue went away and so far it has.
 
Don
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For what its worth, my engine is designed for 95 RON - and it states on the petrol cap there are no benefits to running anything higher.
I'm fairly sure it doesn't say that, although happy to be proven wrong with a photo.

All TFSI/TSI engines (and indeed almost all modern engines) will have knock sensors and will advance/retard ignition based on fuel quality regardless of what a sticker on the Petrol cap claims.
This benefits both fuel economy and emissions and is largely the reason they were fitted.
 
Permabanned
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To be fair I wouldn't be calling people ignorant while claiming changing from E10 to E5 gives you a 1/3rd increase in your fuel economy :p

The math is quite simple, it worked out at 25% Are you exaggerating or do you struggle with basic equations?
I will claim it, because it was my experience.

Claim it bogus, go ahead, you're only doing yourself and the rest of everyone using E10 a disservice to flat out deny someone's experience based on what?
Because I said it on a forum?

If you knew me in real life you'd damn well accept my answer, because you'd damn well respect me.
 
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