I have a 2006 vRS, and the MPG figures on the readout look very good indeed. In fact they're too good. When one calculates the MPG from the actual mileage/amount of fuel, then it's a lot less than the readout.

I noticed this soon after I bought it. I took it into the dealer for its first service last year and asked them to look into it, but they said there was no fault displayed on the diagnostic computer so they dismissed me like some nutter.

Since then, I've been logging all my fills, the number of miles per tank and the computer readout per tankful, then plugging it all into a spreadsheet. What seems clear is that it's underestimating the fuel used by almost exactly 1l/100km.

Is anyone else having this problem? If so, is there a fix?

yeah, it lies

Mines about 6-10mpg out, tbh I ignore it now.

HTH

The later cars, 55/06 on , do seem to have a problem with the fuel computer , over reading mpg , whereas the earlier cars are more accurate , some more than others , mine is pretty good in that respect

when i went to santa pod last weekend 260 mile round trip computer said on the way there i got 67mpg and on the way back 64mpg (was a stedy drive) avarage =65.5 when calculated it was actualy 57ish mpg but thats still pritty good

My computer will regulary return figures around 55-56 mpg, however on calculating actual gallons put in versus miles done it works out around 50 mpg. I think this is the only way to be truely reliable. Still 50 mpg aint at all bad. Picking up my new Octy VRS on the 20th, hope it's returns are almost as good!!

I seem to get a comfortable 500 miles from a tank of diesel, so just say my car averages about 50mpg - trip computer often says I get 60 odd on some journies, but the long term averages is in the low 50s so it seems OK to me. My car has the brains of an 04 vRS in it, so perhaps they were more accurate than the newer ones?

Mine says an average of 44-45 mpg.

I get an average of 44-45 mpg in real life.

I get about 430-440 miles out of a tank average

Mine is a 55 plate and I am perfectly happy with that

Just like speedos, should probably expect up to about a 10% over estimation

If anyone has a TRUE mpg reading , then it should be reported to trading standards as bieng faulty .

I have a 53 plate and it is 4-5mpg optimistic.