2010 v's 2012 Vrs cr TDi Octavia II

[grinder]

Hi, I'm on my 2nd vrs diesel , both bought from brand new, however the latest one seems well down on fuel efficiency compared to the previous one, both cars are identical apart from the colour , I initially thought it could just need a few miles clocked on it untill it settled down but now with 3k on the clock things seem no different.

before running back to the dealer i was wondering if the computer which calculates the mpg could be so different to the previous one as to give 8-10 mpg difference? Its difficult to compare the two by filling the tank and calculating it on actual use as i no longer have the 1st car to do this with.

I do recall the older one giving me 53mpg on a "autobahn" when sat with the cruise control at 90mph ,

whereas the new one will only deliver around 48 mpg at 70mph, and down as low as 40-42mpg when at 90mph, is this the norm?? or was perhaps my older one reading favourable figures?

I'd appreciate your thoughts ,

David

[drefaldwyn]

I wonder if it's been "strangled" by emission regs?

Buy the old car back .... it surely can't be worn out!!! LOL!!!

[Jim1556]

I too am a little disappointed with mine, picked up brand new in January, done 3500 miles now, most of which are motorway @ 80 with cruise on. Computer says 48ish...

I know the book says 49.7 but I rarely give mine the beans as it's a 20k per year mile muncher.

Taking it in sometime over the next week for an oil change, we'll see if this makes a difference...

[Dodgy]

Forget what your old car did, it's irrelevant when assessing your current car's performance. Fill the car to the brim, drive it, fill it again and work out MPG from that. I get roughly 43mpg average which consists of mainly short journeys.

Also, at 3000 miles, your car is nowhere near being run in (in fuel economy optimised terms).

[wraggvrs]

i agree with dodgy wait until youve done 10k + or until you have had your 1st service and see what your getting then...

engine will be run in and more fuel efficient after 10 -15k on clock

[phsroberts]

Yup, mine is still improving at 17k. Averaging about 50-52mpg.

[GriffoVRS]

Hi, I'm on my 2nd vrs diesel , both bought from brand new, however the latest one seems well down on fuel efficiency compared to the previous one, both cars are identical apart from the colour , I initially thought it could just need a few miles clocked on it untill it settled down but now with 3k on the clock things seem no different.

before running back to the dealer i was wondering if the computer which calculates the mpg could be so different to the previous one as to give 8-10 mpg difference? Its difficult to compare the two by filling the tank and calculating it on actual use as i no longer have the 1st car to do this with.

I do recall the older one giving me 53mpg on a "autobahn" when sat with the cruise control at 90mph ,

whereas the new one will only deliver around 48 mpg at 70mph, and down as low as 40-42mpg when at 90mph, is this the norm?? or was perhaps my older one reading favourable figures?

I'd appreciate your thoughts ,

David

53 mpg at 90 mph seems overally optimistic.

With the cruise set to an indicated 78 mph, on a good day I will probably get an average of 50 mpg on the trip computer over a run allowing for the usual speeding up/slowing down (more like 47 mpg actual).

My overall average is about 44 mpg (calcuated) in mixed running.

[Paul007]

These tests must be outside the UK as I thought our limit on motorways was 70....?

[silver1011]

These tests must be outside the UK as I thought our limit on motorways was 70....?

I guessed you missed the "autobahn" in the opening post.

[silver1011]

Do not trust the onboard computer.

It always make me chuckle when people quote particularly good or bad MPG figures because that is what their car is telling them.

Granted the vast majority of computers are close, to within a single MPG or two but the only accurate way of confirming a car's fuel economy is filling the tank, resetting the trip meter, running it down to the red, refilling and noting the pence per litre, miles completed and number of litres used to refill the tank.

Add this data to one of the many online MPG calculaters and that will be as accurate as you'll get.

http://www.torquecars.com/tools/uk-mpg-calculator.php

[Paul007]

Quite. I had.

[dubbers]

Same experience as GriffoVRS

My vRS has just passed 2,700 miles of mainly motorway miles - Just like any other diesel car that I have owned - Cold weather affects economy I get with my 100 mile commute to work.

[HWMBO - Mark]

I agree with dubbers the recent cold spells affected my MPG too but I did notice last week my tyres were a little on the low side but since i've pumped in a few more pounds i'm back upto 50MPG (7500 miles on the clock) on a sensible run & rolling on 33/34 PSI. Worth checking your tyres, it's sometimes the simple things that make a difference.

Edited 24 February, 2012 by HWMBO - Mark

[jrw]

Do not trust the onboard computer.

It always make me chuckle when people quote particularly good or bad MPG figures because that is what their car is telling them.

Granted the vast majority of computers are close, to within a single MPG or two but the only accurate way of confirming a car's fuel economy is filling the tank, resetting the trip meter, running it down to the red, refilling and noting the pence per litre, miles completed and number of litres used to refill the tank.

Add this data to one of the many online MPG calculaters and that will be as accurate as you'll get.

http://www.torquecar...-calculator.php

Wonder who you are talking about here :think:

A lot of people including me use fuelly so perhaps you should start putting your fill ups on there to track?

[Wardy]

Or just tweak the trip computer MPG accuracy with VCDS? Mine is now identical to my brim-to-brim calcs.

FWIW, I'm averaging 47mpg in a tweaked PD140, with quite a mixture of local, A & B road work and motorways.

[silver1011]

Wonder who you are talking about here :think:

No one in particular.

Even if the economy of two identical cars was measured using the same method because fuel economy is affected by so many different variables its so difficult to compare accurately.

Edited 24 February, 2012 by silver1011

[dkgt]

I don't know if this helps but I have a 2011 vRS with 28k on the clock and i have just got back from Italy via Germany and it was pulling 140mph where allowed and we still averaged 46mg from a tank, and that includes hard acceleration when possible.

I agree wait for the engine to run in mine didn't seem to "loosen up" until 15k