I've always read on here how inaccurate the mpg average readings are from the car and always very optimistic, I started using fuelly at the beginning of December and i'm finding the infotainment is actually reading less then what it's actually doing buy upto an average of 1mpg over a full tank which IMO is pretty damn good.  I've actually calculated it myself to make sure fuelly is doing it right and it is.

 

How are other people finding it....

These MPG displays are usually flattering and not so accurate, they can be calibrated with VCDS I think to make them closer to real.  

Cant say I've done it but if the car is showing a correct (or nearly) mpg im happy!

I find mine pretty accurate too. Last fill up was 55.1 on Fuelly and the computer was showing 54.9. Computer is usually within 0.5 mpg, sometimes under, sometimes over but pretty good guide imo.

These MPG displays are usually flattering and not so accurate, they can be calibrated with VCDS I think to make them closer to real.  

 

My point is that my car is doing better than it actually says it is, not by much though.

 

Filled up today and the my car said the average for the tank was 47.7 and fuelly said it was 48.4.

I have done over 8000 miles in my 2L DTI. accuracy is always within +/- 0.5%, ie pretty damn good! 

Sounds like the MKIII may be more accurate than the MkII.

 

My MkII FL vRS CR DSG overall mpg reads 45.8 and the real mpg is 43.59 - so 5% error.  This is over more than 6½K miles of very mixed driving. 

 

More accurate than my last car, a Honda Civic, that read 35.4 against a true 32.6 = 8.6% error.

 

My point is that my car is doing better than it actually says it is, not by much though.

I find the same with mine, based on "consumption since last fill" usually the computer is 1-2 mpg pessimistic. I work it out myself rather than using Fuelly.

Mine is set to display l/100km obv but while the reading for my first fuel-up was way off the reading for my last fuel-up was spot-on so go figure. 

I've never found on board MPG readings to be wrong to be honest, I'd find it odd if it wasn't accurate given that the amount of fuel fed into the engine must be measured/controlled by the ECU so it must be accurate or is my logic completely wrong here?

I've never found on board MPG readings to be wrong to be honest, I'd find it odd if it wasn't accurate given that the amount of fuel fed into the engine must be measured/controlled by the ECU so it must be accurate or is my logic completely wrong here?

You would think so, wouldn't you? But this is my 6th VAG car and the previous 5 all varied between 3 to 10% accuracy for what were essentially the same engine. They must have done something to this one because it is so much more accurate.

Edited 12 January, 201412 yr by ssfan

For our Yeti to average 45mpg fill to fill I need to get around 52mpg indicated on the computer every commute to and from work; about 36 miles each way.

 

TP