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That's pretty accurate. Up to now I've had a wider deviation but not really had the car long enough to say if thats likely to be a permanent state of affairs. I'm sure accuracy is also affected by different tyre sizes as they will have slightly different rolling circumference. My experience with previous computers is they tend to be optimistic though.

I'll definitely keep an eye on this and report back in a few months - it'll take that long for me to rack up enough miles to know :happy:

The computer should be very accurate but I'm not sure why it isn't.

if you base the mpg on the trip meter - it thinks it has done "X" miles and it should be able to measure fuel going in to the engine to within micrograms or it can't set accurate mixture.

So there is no reason I can see why the computer mpg is not accurate.

Yes I agree - different tyres will affect how far you actually travel but the car thinks it has done "X" miles by measuring wheel rotation - not physical distance.
 
The computer should be very accurate but I'm not sure why it isn't.

if you base the mpg on the trip meter - it thinks it has done "X" miles and it should be able to measure fuel going in to the engine to within micrograms or it can't set accurate mixture.

So there is no reason I can see why the computer mpg is not accurate.

Yes I agree - different tyres will affect how far you actually travel but the car thinks it has done "X" miles by measuring wheel rotation - not physical distance.

My Bora displays an average MPG or a live MPG which changes depending on how far you push the loud pedal, so maybe the Leon's computer is showing an average rather than the actual MPG?
 
The computer should be very accurate but I'm not sure why it isn't.

if you base the mpg on the trip meter - it thinks it has done "X" miles and it should be able to measure fuel going in to the engine to within micrograms or it can't set accurate mixture.

So there is no reason I can see why the computer mpg is not accurate.

Yes I agree - different tyres will affect how far you actually travel but the car thinks it has done "X" miles by measuring wheel rotation - not physical distance.
I agree that the computer should be accurate because it knows the fuel pumped into the engine and the mileage. My calculations using the same mileage reading (trip/odometer) based on the fuel put in the tank should match. I keep track of it on fuelly, so will see if long term average on the computer matches fuelly. Tank by tank differences may be accounted for by differences in what I think is 'full'. I've only filled it three times so far and each one has shown the computer to be out by 2-3 mpg.
 
My Bora displays an average MPG or a live MPG which changes depending on how far you push the loud pedal, so maybe the Leon's computer is showing an average rather than the actual MPG?
Leon can show live MPG, average MPG since start of journey, average MPG since refuel and a 'long term' average.
 
i hit 62.3mpg ave since start on mine today...
Why is it better on a warmer day ???
Same 40 odd mile journey returning this evening got max of 56mpg

That's a 184hp 2014 FR with two folks in & not much else.
cars only done 5700miles mind

Just to add most of this Driving was on on the A1 & at the speed limits most of the time
 
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i hit 62.3mpg ave since start on mine today...
Why is it better on a warmer day ???
Same 40 odd mile journey returning this evening got max of 56mpg

That's a 184hp 2014 FR with two folks in & not much else.
cars only done 5700miles mind

Just to add most of this Driving was on on the A1 & at the speed limits most of the time

A lot for parameters could be the reason - some of which are
http://wxbrad.com/why-cold-weather-gives-you-lower-gas-mileage/

On my 2.0 150 - theres about 2-4 km/l difference when driving during winter and summer.
 
Whats the explanation forv warm weather increasing mpg figures so much?

Basically - warm air is less dense so it requires less fuel to make the correct fuel/air ratio.

This is why your car feels more powerful when the air is cold - the cold air with more fuel can be packed in to a cylinder better and it gives more power.
 
So I get the possible reasons are warmer air the car warms up quicker blah blah blah,
But it does make a fair difference I noticed this on the Mk1 FR just the same.
Yet if its that good why do we need Intercoolers then for the engine... Then?

Cold Air is denser so burns better right?

But for everything else it seems as its just a MPG looser when its actually cooler weather

Going on a 400+ mile trip this weekend motorways the lot so will see what it averages.

Miss the 650m Tank Range of the Mk1 mind...

or 740m with additive in !!!

lets see if I can get nearer 600 on a run. if I can manage to brim the tank.....
which is another faf with that poxy plastic restriction thingy which I still need to remove. [:@]
 
I got 47 mpg on my trip computer on a 44mile trip without trying.

1.8 tsi aswell so impressed.
 
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I did a round trip (1.4 FR) from Middlesbrough to Norwich last weekend, including some local town driving, and got 475 miles out of the tank, I was running on fumes by the time I got home though!

Not sure if this is good/bad mileage, but I wasn't hanging about on the few stretches of dual carriageway in Lincolnshire/Norfolk.
 
I did a round trip (1.4 FR) from Middlesbrough to Norwich last weekend, including some local town driving, and got 475 miles out of the tank, I was running on fumes by the time I got home though!

Not sure if this is good/bad mileage, but I wasn't hanging about on the few stretches of dual carriageway in Lincolnshire/Norfolk.

Good result - X2 - mpg and the football
 
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