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We all know what the book says your official mpg should be...I've just checked mine for the past 2000 miles. Mostly, I do short journies ( 2-3 miles to work each way ) but I was surprised at 32mpg.

Just goes to show, don't buy a diesel expecting to get 45+mpg if you're gonna sit in school-run traffic each day
 

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There is actually a setting in VAG-COM that allows you adjust the mpg that the computer reports to reflect your real world driving.

Just count yourself lucky you are not in an R32 you would probably be getting 25mpg.
 

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Having driven the euro cycles on which the mpg cycles are based (on a dyno with a trace), the reason the are so far off from real mpg is that the cycles are in no way representative of how anyone drives. For instance, only ever gets to about 2/3 throttle, and the speeds are low and in high gear. A picture of this is shown below. The federal trace is a lot more realistic, since it was based on data recorded by some guy and his car!

Posted Image
 

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Well I run a contiuous check on mpg. My 150PD averaged around 45 over 40K+ miles. My 2.0TD is averaging around 49 after 10K. Mileage is probably 85% extra urban, (enthusiastic non-motorway!), 15% urban. Living where I do, the traffic is never too bad.

"Official" figures are too easilly massaged and should be a lot more independant of manufacturers.
 

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I run a continuous check too - on a spread sheet - I know it's sad but I want to know how much the car is costing me and the average is well behind the OBC in reality. I'll check tonight when I get home but I'm fairly sure the real life mpg for the Golf over 40k miles is 39mpg - to compare to my old 320d it's within 0.5 point of that too.
 

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There is actually a setting in VAG-COM that allows you adjust the mpg that the computer reports to reflect your real world driving.

Just count yourself lucky you are not in an R32 you would probably be getting 25mpg.
I don't suppose you know how to do this do you?
 

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Richards spreadsheet is far too complecated for my little brain, so I adapted it to a simple version!

Basically mine tells me I am getting an average of 55.32mpg. This includes all driving as it goe's by how much I put in the tank and how many miles I have done.
 

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There is actually a setting in VAG-COM that allows you adjust the mpg that the computer reports to reflect your real world driving.
I don't suppose you know how to do this do you?
Sure do..

SELECT 17 (Multifunction Instrument Cluster)
Coding -> Function 10

-> Channel 03 (MFD Fuel-Consumption-Indicator)
The base value is 100 it can be adjusted in 1% steps. The respective min max values are 85 (%) and 115 (%).

Use the "pencil and paper" method to get your real world mileage.
Start with a completely full tank.
Record the mileage, # of gallons to completely fill and, the MFA fuel mileage. Reset the MFA mileage and trip odometer reading before you start the car & pull away from the pump.
Record 3-5 fill-ups worth of information and calculate the real world #s for fill-up #2, 3, 4, & 5. NOTE you have to completely fill the tank every time or the #s are worthless.

Average the MFA #s and the "real" #s separately.
Calculate the % difference between "real" and MFA.
% deviation = (((measured ? true) / true) x 100 )
The % difference between the "real" and MFA is the adjustment that will be needed in channel 3.

Increase from 100 to reduce the MPG reading.
Decrease from 100 to increase the MPG reading
1 point = 1% change
SO if AVG Real True= 44 and AVG MFA Measured = 50 the difference is 14%.

You would then change the channel 3 value from 100 to 114.
Enter your new number in "new value:", click Test, then Save.

Drive and recheck your MFA against paper it should be reasonably close.
 

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my current tank is averaging 25.5mpg!

still better than the scooby which was doing 18mpg.

this is all mainly going to work which is a very short journey.

almost pointless in fact so will start walking when the weather is better.
 

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Mines giving me 29.1 mpg as i worked it out via the good old
calculator, im a bit dissapointed with that, as its no more effiecient
than my 1.0 litre corsa lol and i used to rag that quite a bit, but i
also have to say the 29.1 mpg achieved was done by fast driving i.e
hold the gears up till about 4k rpm on a diesel [:$] lol

Sat [y]
 

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We all know what the book says your official mpg should be...I've just checked mine for the past 2000 miles. Mostly, I do short journies ( 2-3 miles to work each way ) but I was surprised at 32mpg.

Just goes to show, don't buy a diesel expecting to get 45+mpg if you're gonna sit in school-run traffic each day
You should'nt have bought a derv for short journeys. 2-3 miles isnt even giving it time to warm up and time to produce the best mpg. Thats why you are getting poor mpg. Dervs are great for long haul and good for long journeys, wether they are round town or not.

In my last job i had to travel 20 miles to work and back, all motoway and if i took my time i could easly see 60+mpg, now i travel 5miles to work and oftern see 41-45 and thats on a 150k 115pd.

Also you must remember your car is brand new, and you wont be seeing better mpg figures until you hit 10k.
 

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Discussion Starter · #13 ·
I have a diesel for tax reasons - not economy reasons. Ideally, i'd have had a GTi but it would have cost me an extra ?100pm in tax.

PS - the car isn't brand new - its a year old with nearly 20K on it[:D]
 

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Petrols are the same on short journeys - no doubt due to the fuel mixture requiring to be richer when the engine is cold. Those of us old enough will remember the hassle of a manual choke on a car.

In mine, when I get to the end of the road and the trip computer first shows ave mpg it reads ~18mpg! This gradually increases until I get to work, 6 miles all <30mpg when it is about 36-37mpg.
 

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There is actually a setting in VAG-COM that allows you adjust the mpg that the computer reports to reflect your real world driving.

Just count yourself lucky you are not in an R32 you would probably be getting 25mpg.
25mpg! I wish, I only get 21mpg in an average week!!!! [:(]
 

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Richards spreadsheet is far too complecated for my little brain, so I adapted it to a simple version!
Cheers Graham, now I've spat beer all over my screen. That wouldn't normally matter but this one's mine!
 

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According to mine its averaging 42.9mpg over the past 9k, thats on a mixed 15 mile a day trip. The car is on 29k. I'm tempted with a GTi or Focus ST since they seem to get into the 30's
 

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According to mine its averaging 42.9mpg over the past 9k, thats on a mixed 15 mile a day trip. The car is on 29k. I'm tempted with a GTi or Focus ST since they seem to get into the 30's
Small point but rember the "continual" memory function (mem 2) resets after some time. Think it is 2k miles or 100 hours, whichever comes first.

Think you would be lucky to get into the 30s for the ST.

Official figures are:

20.5mpg urban [:O]

41.5 extra-urban

30.5 combined
 
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