537playing

Why is my speedometer off by two or three miles higher?
My radar detector in my other three cars is spot on but in the Audi A6 is is off. Very annoying.

Superfly_A6

don't lose your hair over it. this is normal.

qqq1970

All German cars I owned in the past are like that. They purposely set the speedometer 2 to 3 miles higher so you are always under posted speed limit if you drive at the limit. In my old Merc I can press a few buttons on and it can show the real speed and a whole bunch of other technical info on HVAC display.

snagitseven

Also, it's likely your computer MPG will read high as well. That one however, unlike the speedometer, can be adjusted with the VCDS (Vag-Com) cable and software.

DeerHunter

Tangential question: Has anyone been able to use VAG-COM to enable GPS-derived speed in the Nav screen? Even the cheaperst Garmin has this capability and it would be a useful option for us optimistic German types.

TJKs '02 2.7T

I also noticed that my speedometer reads around 2-3 MPH below what my Waze App is reporting...probably better this way versus under reporting the speed. However, more annoying is the MPG errors...my '02 A6 was always off by at least 2 MPG and after my first reading on my new '13 A6 it came in again at 2 MPG over the actual.

The good part though is that I attained 25.8 MPG...better than I ever got on my prior Audi over 10 years...there have been times where it is shown on the "Short-Term" getting 34 MPG over a trip.

snagitseven

As I mentioned a couple of posts ago, the DIS MPG consumption display can be adjusted to more closely match your real world calculation with VCDS:

Correct Consumption in DIS program
[17 - Instruments] [Adaptation - 10]
Look about 20 items down on the drop-down list for "Correct Consumption" and select it
Change 100 to xxx
Example - if your DIS is consistently off by 7% to your actual calculated mpg:
You RAISE the number to the percentage if DIS is OVER reporting mpg (i.e. 107)
You LOWER the number to the percentage if DIS is UNDER reporting mpg (i.e. 93)

snagitseven

I've not seen any, probably because there's no MMI software code to support the feature.

twentysevenlitres

Speedos reading over actual speed is a design rules thing.
In most countries speedos are allowed to have an error of 10% bit must not read under the stated speed.
Most manufacturers err on the side of caution and have to them read slightly over.

Also saves on any litigation issues ("but my speedo said I was doing 55 officer"!!).

Both my Audi's are a damn site more accurate than any of my GMH products in the past - 1-2% under vs 8% under - no wonder I'm always overtaking Falcons and Commodores on the freeway...

Excerpt from Australian Design Rules:That's actually 10% + 4km/h, which is even further out (14% at 100km/h)

edit: bold = corrections of tense

dicktahoe

I think you may be reversing Speed reading with Odometer reading. Odometers are not permitted to read high. That is--they cannot indicate you have traveled 105miles when you only went 100 (that would reduce your warrantee for one thing). But the Speedometer reads a few mph higher than you are actually going. When I read 75mph, my GPS says I'm only doing 72. That keeps you from unintentionally speeding.