Inaccurate Odometer

[Philler Cap]

Hi folks. I have recently changed my B6 for an Alltrack and, because I claim mileage on many journeys, I have noticed that the odometer reads about 4% less for the same journeys (the mileage previously recorded also agreed with distances given, for example, by Google Maps). It struck me that this is probably down to the larger wheels, which, although fitted with lower profile tyres, still have a greater rolling radius (Alltrack: 225/45R18, previous B6: 215/55R16). It seems that VW haven’t changed the calibration and, presumably, the speedo is also out although I can’t tell so easily.
Has anyone else noticed this issue and does anyone know whether the calibration can be changed via VCDS? :1zhelp:

[Guest 2]

That's pretty odd.

Does the 225/45/18 coincide with the tyre sizes listed in the fuel filler flap or drivers door jam?

[Philler Cap]

That's pretty odd.

Does the 225/45/18 coincide with the tyre sizes listed in the fuel filler flap or drivers door jam?

Yes - wheels & tyres per spec (and an option inside fuel filler flap & selected option in tyre pressure monitoring menu).

[Guest 2]

Take it back to vw any explain as the car is still under warranty.

Also ask to take a similar car out on a run and compare the mileage on the two different cars.

[Sam]

Does the mileage in the ECU match the mileage on the odometer?

Ross-Tech: VCDS Tour: EDC-15-16 Mileage (http://www.ross-tech.com/vcds/tour/EDC-15-Mileage.html)

It's common for it to be 'close' but if your readings are wildly different then this may highlight an issue

[Philler Cap]

Thanks both. I've already sought advice from my main dealer - they didn't know what they could do about it & didn't think VW would allow them to make any adjustment related to the odometer! I don't actually have VCDS so can't comment on the ECU calculated mileage.

[Guest 2]

Ask for another Alltrack for a couple of days and see if it logs the same mileage, if its the same then its a Passat problem (lol) and not your particular car.

[Philler Cap]

Ask for another Alltrack for a couple of days and see if it logs the same mileage, if its the same then its a Passat problem (lol) and not your particular car.

Chances of my local dealer having another Alltrack available are slim, and I was asking for other people's experiences to try and glean whether it was a general Passat problem or my particular car. :beerchug:

[CovRob]

... I was asking for other people's experiences to try and glean whether it was a general Passat problem or my particular car. :beerchug: I think the difficulty will be in finding someone else who has swapped similar models AND who monitors mileage with regularity on repeat journeys. I can't assist I am afraid, although Hadwins of Lindale do have an Alltrack demo if you are in the Northwest

[Guest 2]

A dealer can get any car in for a customer requires for any purpose, be it a specific courtesy car needed or for a demo, just ask.

Audi got me a SQ5 from MK for a 1 hour test drive, no one else drove it, just me and then it was returned.

[DSG4ME]

Check it against what a sat nav says, the difference shouldn't be more than 3mph.