MK5 Golf GTI

All Things Mk5 => Mk5 General Area => Topic started by: stu_no_1 on August 06, 2010, 02:05:05 pm

Title: Trip computer not accurate
Post by: stu_no_1 on August 06, 2010, 02:05:05 pm
My average mpg on my trip computer is miles out when it says 20mpg its really about 25mpg when i work it out on how many miles i got from so many litres has anybody else got this problem and can it be fixed the funny thing is the miles till empty is quite accurate so i just go by that
Title: Re: Trip computer not accurate
Post by: big al on August 06, 2010, 03:11:29 pm
Have you pressed the reset/ok buton on the bottom of the stalk by accident? On the screen there should be a number 1, if there is a number 2 then it is showing average MPG, etc.
Just press the button once and it should change it back for you.
Title: Re: Trip computer not accurate
Post by: Richn83 on August 06, 2010, 04:03:43 pm
The computers are generally a bit in accurate, the speedo itself is generally in the region of 10% out, the computer will also be rounding off figures, and have a sampling rate which will all add in-accuracies there is an ability to add a correction factor in VCDS for the speedo not sure if this would also alter the consumption value.  :happy2:
Title: Re: Trip computer not accurate
Post by: stu_no_1 on August 06, 2010, 07:53:12 pm
Have you pressed the reset/ok buton on the bottom of the stalk by accident? On the screen there should be a number 1, if there is a number 2 then it is showing average MPG, etc.
Just press the button once and it should change it back for you.
no ive not pressed anything by accident i know how it works it just it always read about 4 or 5 mpg lower than im getting the highest ive ever had was 30mpg but i done nearly 400 miles on the tank this worked out at nearly 40mpg so im thinking its maybe a percentage out as the gap has got bigger as the number it displayed got higher
Title: Re: Trip computer not accurate
Post by: stu_no_1 on August 07, 2010, 08:03:56 am
anybody help me out with this?
Title: Re: Trip computer not accurate
Post by: vRS Carl on August 07, 2010, 10:07:24 am
You can accurise the Trip Computer.

Work out the actual MPG figure from a full tank

Number of litres added / 4.54 = number of gallons used

Actual MPG = distance on full tank / gallons used


Go into VCDS/VAGCOM, open controller 17, Instruments

Click advanced functions, Adaptation box 10

Scroll up to channel 3

Standard default value = 100%. This can be altered withing the range 85% to 115%


Work out new value this way:

New % figure = (old % figure x MPG figure shown on dash) / calculated actual MPG figure

I have done both my cars and it's pretty much spot on now  :happy2:

Disclaimer: Neither I nor MK5GolfGTi will be held responsible if anything goes wrong. If you do this procedure you do so at your own risk!
Title: Re: Trip computer not accurate
Post by: vRStu on August 07, 2010, 10:29:07 am
I've added this to the VCDS Tips & Tricks Carl  :happy2:   :notworthy:

http://www.mk5golfgti.co.uk/forum/index.php/topic,121.new.html#new
Title: Re: Trip computer not accurate
Post by: vRS Carl on August 07, 2010, 11:42:52 am
Cheers Stu :happy2: