[Jimmer]

Has anybody compared fuel consumption between E10 and E5. On mostly urban driving, a very rough check on my Xceed 1.4 DCT shows a reduction of about 4 miles per gallon. Deciding to take this further my rough back of a *** packet (remember those) calculations suggest that any reduction greater than 2 MPG would make Super(E5) fuel a better proposition. This is based on E10 @ £1.43 ltr and E10 @ £1.50 ltr. Just wondered if anyone has any figures that agree/disagree.

 

[Back again]

E5 round these parts is nearer 15p a litre more on average. The local BP sells E5 for £1.679, E10 is £1.459, thats 22p extra.

A rough check is no good. You needed to have figures over several months before the swapover to compare with the after to have anything worth while.

Then there is the fact that over the colder months our mpg falls. Its normally worse on diesels but it does affect petrols as well. Looking at the wifes car over the past couple of years the mpg between October and March has been about 3mpg less than April to September. Mine was nearer 4 mpg over the same period. Will tell you next year if E10 has made any difference, its too early to tell.

But at 15 a litre extra I doubt I will be bothering.

 

[iooi]

It really is pointless trying to compare MPG on a car now, unless you have figures from the same time last year.
Lower temperature's is the major cause of MPG going down.

 

[Jimmer]

I realize that to get results accurate to the N th degree far more input would need to be needed, but this was never intended to be scientific study. I was just trying to obtain ball park figures to help decide the economics of me continuing to use E5 and paying the price or changing to E10 and wondered if anyone else had done the same.

 

[iooi]

I get that, but my mpg has taken a big hit purely to the weather. Which is something I see every year around this time due to car taking longer to warm engine up.
So trying to factor in difference due to E10 & E5 is not easy.

So to really tell you are going to have to run a tank of E10 to empty, then a tank of E5 and see the difference.

Only thing is round here it's a 12P difference between E10 & E5.

 

[macgd016]

As others have said you would need to use both fuels over several tank fulls as well as similar driving and weather conditions to get a realalistic view of what mpg difference there is between the two. I've tried a couple of tank fulls of each back to back and get the feeling Shell V Power RON99 is giving me more mpg but my main reason for using it is that my car seems to run quieter and is a little bit crisper to drive. I also believe that long term the premium fuels are better for the car, none of this is scientific but as the cost is not a factor for me so I will use RON99 where I can

 

[fabz]

I get that, but my mpg has taken a big hit purely to the weather. Which is something I see every year around this time due to car taking longer to warm engine up.
So trying to factor in difference due to E10 & E5 is not easy.

So to really tell you are going to have to run a tank of E10 to empty, then a tank of E5 and see the difference.

Only thing is round here it's a 12P difference between E10 & E5.

I found this post because I was actually looking for someone with similar issues.

I have the Xceed 1.4 and my MPG reduced considerably recently. This was after the 2nd service was done, but it also coincided (+-) with the change to E10. I used to do 47mpg(this was the overall for 10k miles) and now it's around 41mpg.

I suspected it could be the E10, so I did exactly that. A full tank of E10 and then a full tank of E5. The difference was 0.7mpg. I did the same commute in 2 different weeks.

Could it be it's just the E10 plus the cold weather? A decrease of 6 mpg is a lot.
Could the service have anything to do with it as well?

 

[maxaret]

Depending on your driving/routes/distance routine the loss of MPG in cold weather can easily be 5 MPG ish.

 

[Back again]

If you want a real reduction of mpg/range consider a PHEV.

Our round trip to Tesco is 12 miles. During the summer months that used 12 miles of range. Last Friday on a cold morning (but not as cold as today) those same 12 miles used 20 miles of range.

But still way cheaper than petrol, cost about 40 pence in electric, petrol at 40 mpg would have cost £2.

 

[iooi]

If you want a real reduction of mpg/range consider a PHEV.

Our round trip to Tesco is 12 miles. During the summer months that used 12 miles of range. Last Friday on a cold morning (but not as cold as today) those same 12 miles used 20 miles of range.

But still way cheaper than petrol, cost about 40 pence in electric, petrol at 40 mpg would have cost £2.

Or a HEV.

Trip by trip between summer & winter can easily see a 10 to 20 mpg drop over a usual 6 mile run to supermarket & back.

Did a good run yesterday & decided to watch engine temp to see how long to get to normal. After about 2 miles. It had gone up 2 bars. Stopped at lights & it then went down a bar.
In the end took over 6 miles to get up to normal.

 

[fenegroni]

I have filled regularly with Shell V-Power (E5 petrol) because my experience with past cars has proven longevity of the engine.
I had an rx-8 which actually preferred lower RON petrol, but would accumulate deposits on the engine outports if supplied with a bad batch of lower quality fuel, which was obviously completely random, but more likely when filling up with regular unleaded. I can only infer that the extra detergents and the slightly stricter quality control contributed to a better running engine.
But as I said, it felt more eager on lower 95 RON and indeed, on the occasion I found higher ethanol content at the track, it was delivering power even more linearly.
It was a non-turbo engine though, and needed all the help it could get to ignite!