I have just done a 'brim-to-brim' economy calculation over 550 miles on my TDI 130 estate, and found that it was 54.8mpg. The computer had recorded 55mpg.

This seems very accurate, and I'm rather surprised because on the whole people seem to find that the computer give a more optimistic reading.

Is this unusual?

My mpg per the car is consistently 10-16% over optimistic.....

My Fabia vRS was consistently 20+% over-reading...

My Octavia vRS over-reads by exactly 0.8 MPG

I checked mine manually for the first few tanks - it was pretty much on so I decided it was close enough!

It reads in litres/100km now which confuses me!!

Em, no. The "tank mpg" mode typically over-reads by about 10%, which seems odd cos the "expected range" mode is usually pretty accurate after you've had the engine running for 5 minutes (presumes car is moving off soon after started).

So how did the "expected range" mode on yours read?

Call me sad...

2000 X SLX TDi

Ok, I'll call you sad, but not as sad as me when I saw that the best ever fuel economy of 44mpg I saw on my vRS wouldn't make it to the lower reaches of your scale!

But your car is more fun than mine!

If you want to see something more depressing I can post a graph of fuel prices over the last two years....

Although brim to brim gives you an accurate measure of fuel used, I'm assuming your only method of measuring distance travelled was the Odometer or Trip Meter. So any inaccuracy in that would lead to a false MPG figure.

I'm still struggling with the fact that I can spend £70 filling a tank that wasn't quite empty.

That's a fair point.

My main reason for keeping track of fuel economy is that this is usually a good early indicator that something is going wrong with the car, as I have to fill up every week.

But your car is more fun than mine!

If you want to see something more depressing I can post a graph of fuel prices over the last two years....

Yes please

My average MPG on the trip computer is about right when I compare it with the manual record I keep of mileage done and fuel used at each fill up which is about 53 MPG.

My current trip MPG is about 10% over as I can get it to consistently report 58-60 MPG on my daily commute (78 mile round trip, 85% motorway).

However, when I think back to the 27.5 MPG average I used to get on my old 2.9i Granada V6 I shudder to think how much it would be costing me to fill up every 6 days (15.5 gallon tank)!

I think that's pretty acurate. My pd130 over-reads by 2mpg on the average (trip 2) when compared to the brim to brim method and I usually get 43-45mpg brim to brim although if I drive at 50mph-55mph I can average 49mpg brim to brim.

SWMBO's fabia vrs is usually about 10mpg-12mpg over the brim to brim method.

As requested...price for deisel in Worcestershire....

Ok, I'll call you sad, but not as sad as me when I saw that the best ever fuel economy of 44mpg I saw on my vRS wouldn't make it to the lower reaches of your scale!

i use to write my mileage down on my receipts years ago when i had a motorbike so i could spot any problems etc.

I gave up doing that a while back as it was just depressing me to look at how much I spend on fuel a month. I think it was something like £700 for May/June when I was up north a lot. Absolutely crazy. Diesel in Ullapool just now is 145 a litre! People didn't kick enough fuss up globally when things started going skywards and now there isn't much sign of it slowing. As a result everything is now more expensive, not just driving the car. When I started to drive a whole 6 years ago, fuel was 60.9p at the bottom of the road and now it's double that.

As requested...price for deisel in Worcestershire....

:eek:

Thats scray - most of the increase is this year too. :-(

My calculated mpg and the computer version are usually pretty close. It is scary how fuel prices have shot upwards in recent months. What I want to know is why fuel in my area (Cheshunt) is consistently more expensive than either Harlow or Watford. We're not talking about a penny per litre either, nearer 4-5p/litre on occasions.

We have lost many filling stations to developers, but I think a lack of supermarket competition is a likely factor. It was 121.9 p/litre when I filled up last Friday. In Harlow on Saturday morning, 116.9 p/litre. That's extortion! We have Tesco and that's it, a Sainsburys or ASDA might help inject bit of downward pressure on prices.

I checked mine manually for the first few tanks - it was pretty much on so I decided it was close enough!

It reads in litres/100km now which confuses me!!

it can be changed on the settings (units) on maxidot. but basically the lower the number the better where as mpg higher the number the better:thumbup: