Does anyone know how the MPG calculator works?

[Plyphon]

Hiya,

Does anyone know if the MPG calculator/display is based on actual consumption, or assumed consumption?

As in, if there is a fault with the engine or something that would effect MPG, would that show in the display as reduced MPG, or would the car assume it's getting "X mpg at Y speed" and still display usual MPG?

Does that even make sense... ha ha.

[Guest2]

Hey, no answer to your question im afraid but i would love to know the answer! Id love to know if it calculates air-con usage in it too! Everyone also says having the window open is -10% economy but would that show up too?

[sciroccorich]

I have a good mpg app on my tablet in which I enter the price per litre, quantity of fuel purchased, the date and my current mileage. I add this data to the App every time I fill up and it gives you all sorts of statistics like average MPG, average fuel cost per day and all sorts of interesting data (ok some stats are not that interesting).

I compared the average MPG shown on the App (which is pretty much fact), to the MPG shown on my Scirocco's dash and it is spot on (30.5 MPG)

Your dash display also gives you a real time MPG which drastically changes when you accelerate and coast, this maybe useless to the driver but I predict that it probably does monitor your revs, speed, current mileage and fuel remaining, then does pretty accurate calculations on your MPG..........mine seems to!!

Hope this helps.

[Roy_01]

On the tdi fuel pump sits a fuel metering valve for controlling the injection quantity. With the car can calculate the km/l. When the airco is switched on the fuel economy drops clearly.

[Plyphon]

Cheers, I see, so the car should reflect real usage. Good to know as it puts my mind at ease that I'm getting proper MPG

[Roy_01]

If its not correct you can correct the mpg value with vcds in module instrument, adaptation, fuel consumption.
I have it set on 107% because the mpg value was a bit to optimistic.

[Fifer]

Thanks for that - mine has always read about 5mpg high. I tend to get around 50-53 mpg and the display always claims 55-58.

[selleym]

If its not correct you can correct the mpg value with vcds in module instrument, adaptation, fuel consumption.
I have it set on 107% because the mpg value was a bit to optimistic.

Can i turn it the other way so that it shows 20mpg more?

Just to keep the misses happy

"Hey look my car is economical look 60mpg"

[Roy_01]

[17-Instruments]
[Coding - 07] > [Adaptation - 10]

Scroll down about 20 items in the drop down list until you see something like fuel consumption adaptation - change the value from 100 to higher or lower:

>100 = correction to less economical mpg
<100 = corection to more economical mpg

Just correct it with a few % at a time and look after a refill to check the the average mpg with the filling quantity.

[Billc]

Mine's also about 7% optimistic measured against actual fill ups and mileage.

[Roy_01]

Ok than you have to set it at 107%.