[Asterix]

Went for a trip last Friday. The tripcomputer showed 287,9 km when back home.

Just tried to make the same trip with a routeplanner, showed 287,0 km.

Running on the standard size tyres 185/65-15 I'm very satisfied with that. 

Have you guys ever tried to compare as above..

Forgot to mention: Summertyres are 195/65-15, so I'm looking forward to make same comparison when I get them fitted again...

[AlanHo]

I doubt that a route planner would be a suitable comparison in our area - too many road islands for the car to negotiate which I doubt the route planner would take into account. I did once make a comparison using Garmin Mapsource firstly on a motorway when Mapsource was 1.8% shy of the odometer and once on urban roads where the difference was more that 3%.

I know my odometer is reading 2.5% under - after checking it over a 100 mile stretch of the M5 motorway using the distance boards set at exactly 1 kilometer intervals from the start of the motorway.

[syecadelic]

not something I have ever thought about.

But i know if I put fuel in the car, more so when the car is near empty, that less than 7 litres tends not to move the needle or change the readout on how much fuel is left in the tank. Tend to use it only for the miles covered, I think its pretty spot on, by using a google map for the route, and driving it it tends to be accurate enough

[Asterix]

The only reason I didn't compare with the sat-nav, is because I forgot it at home...

I will try to remember the sat-nav next time i have a longer trip.