Howdy,
What have I done?
Firstly as I have said, I have not done the distance calibration so no doubt "distance to empty" figures will be wrong.
The UG fuel consumption figure was about 5% optimistic (using 5% less than actual). By that stage I had probably filled up about 5 times & did not keep a tally of the litres/gallons pumped into the vehicle over the 5 fills.
Lets say the UG said I used 500 litres/110 gallons over those 5 fills, I manually increased the number of litres/gallons by about 5%. To do this I did the following:
1. After filling the tank, held the up key to recognise fill up.
2. Zeroed the average. Select MPG. Menu - Gauge/Page Menu - Zero Ave MPG,G/H
3. Increased the total number of litres/gallons pumped. Select Menu - Vehicle Set Up - Calibration - Calibrate MPG/Fuel and increased my 500 litres/110 gallons to 525lt/115.5 gallons.
This increased my calibration figure. Say from 5.1 to 5.8 (I have them written down but not handy at the moment)
Unfortunately the adjustment was too much & the UG was then reading about 8% high.
At the next fill I went through the process again but this time reducing the total amount of fuel used. This decreased the calibration figure to say 5.4. Now UG reads about 2.5% high.
Today I filled up again & again reduced the total fuel used but only by a very small amount & the calibration figure is say 5.35.
I just made sure to write down the original calibration figure & if all goes pear shaped, I can revert back to the original figure (by adjusting the fuel used as per the above).