I have undertaken the same long journey twice in recent days with and without passengers and carefully noted fuel consumption. The journey was from Huddersfield to the NEC and back ( to see the Grand Designs exhibition which was very good), a round trip of 214 miles. Fridays trip was just me and apart from the horrendously long roadworks in Notts ( 15 miles long....) was an easy run cruising at just under 80mph when ever possible. Return journey leaving at 6.00pm was hell until south Yorks and took over 30 mins longer..... MPG was 59.5. Also went to NEC Sunday with 2 adult passengers and few hold ups each journey taking under 2 hours and same driving speeds, MPG was 57.5. Shows what weight can do to economy. Weather conditions were pretty similar although possibly more wind yesterday.
MPG Comparison/Observations
- Thread starter Adrian888
- Start date
Also dont forget if your driving with lights, radio etc etc, then you'll use fuel as a battery drain puts a resistance on the alternator and thus the engine... and with being a small engine will affect it more. I find when i'm not using any electrics in daylight I once got 139 miles to £10, but this winter has been poor with probably only getting 110-118 miles..... Bring on the summer!!
Twice a week I do the same 150 mile journey. It's mostly dual carriageway with a few roundabouts every 20-30 miles. I drive off-peak hours.
Lights and heater on:
@70mph = 60mpg
@60mph (mild temp) = 70mpg
@60mph (cold temp) = 65 mpg
@60mph (mild temp, strong wind) = 65mpg
I'm looking froward to driving in the warmer day light weather.
Lights and heater on:
@70mph = 60mpg
@60mph (mild temp) = 70mpg
@60mph (cold temp) = 65 mpg
@60mph (mild temp, strong wind) = 65mpg
I'm looking froward to driving in the warmer day light weather.
a2sumo
A2OC Donor
i definitely see a drop in mpg in the cold of about 4-5 mpg.i put this down to the engine taking longer to get up to operating temp and the additional load on the alternator.
but adrrian888 " Shows what weight can do to economy" oh poo I'm scuppered then! ha ha ha. last year we holidayed in a cottage in Cornwall so had the car very full--back seats down with cases and camping gear(a2oc camping weekend).on the drive down and back to Essex i was really surprised to still get 49mpg on average over the whole trip.
so roll on the summer mike
but adrrian888 " Shows what weight can do to economy" oh poo I'm scuppered then! ha ha ha. last year we holidayed in a cottage in Cornwall so had the car very full--back seats down with cases and camping gear(a2oc camping weekend).on the drive down and back to Essex i was really surprised to still get 49mpg on average over the whole trip.
so roll on the summer mike
the grim reeper
A2OC Donor
Well not sure how accurate it was as never had time to fill up, went to Halifax on saturday using my new Garmin sat nav its got eco challange on it, you put in cars details (mpg's for town/city and motorways) then it tells you how you are doing i set mine at 65mpg's for motorway and 50 for city and it said for the journey 212 miles 63.5 mpg's £15 which i didn't think was to bad as i've only driven around town for the last 2 months.
better than my friends car we went to pick up though. He bought a S430L and he was getting 14 MPG's i think he used more fuel than me on the way home than i did there and back LOL
Phil
better than my friends car we went to pick up though. He bought a S430L and he was getting 14 MPG's i think he used more fuel than me on the way home than i did there and back LOL
Phil
Black Pearl
Member
Hi Adrian,
MPG Sounds very good for the cold weather! and 80 mph. Do you have Dis or are you brimming it?
Am I correct in thinking that you have a chipped 75bhp car? and have recently changed from 17's to 15's?
Another member noted the effect of using the electrics on MPG. My father has a faulty webasto diesel heater on his Merc, so last week we went to have it serviced and there was lots of official webasto info on the heaters.
Basically the webasto on an A2 uses around 0.5ltrs of diesel per hour. On a run I reckon you cover around 60 miles in an hour, and therefore at this time of year the engine is using 4 litres per hour, and the webasto the other 0.5 litre making 60mpg.
In spring therefore, with the webasto off, and AC off, you should get 67.5mpg. The webasto costs around 7.5mpg.
Nick
I'm not sure it's as clear as that. After 10mins or so, when the car engine has warmed up I suspect that the webasto will turn itself off, since heat can then be taken from the engine direct.
Just a guess.
Nick, since then my economy has increased dramatically and more than the cold winter weather normally accounts for to the point where I am lucky to get 50mpg now. I am hoping to fit the 15's today with Goodyear 'Efficient Grip' tyres and tomorrow have the 5th gear upgrade work done by Mike. In addition I will be running a few tanks with Millers fuel additive to try and resore economy and if necessary clean/replace the MAF.
I only use DIS as a guide and ALWAYS fill to the brim and calculate agianst mileage driven/covered. My figures are all taken from actual usage not DIS calculated ( although DIS is within -2/0mpg accurate in my experience).
I only use DIS as a guide and ALWAYS fill to the brim and calculate agianst mileage driven/covered. My figures are all taken from actual usage not DIS calculated ( although DIS is within -2/0mpg accurate in my experience).
dan_b
A2OC Donor
I rarely get more than about 45mpg in my TDi - even on the last tank which was more m-way miles than normal and with the aero bits fitted I managed barely 48mpg brim to brim -was hoping for better I must say.
I've recently replaced the coolant temperature sender (although it still won't hit 90C), the MAF was changed last year, the injector loom was recently replaced, and I run with Millers through every tank. Am on Winter 15s (so one might allow that the stickier winter rubber will have an effect) and of course winter diesel is also formulated differently to prevent freezing, so that will be impacting, along with the aforementioned points about running with the heater/ screen demister/ lights on more. Maybe the return to warmer weather will help, but I think I will still go for the 5th gear mod in the coming months.
I've recently replaced the coolant temperature sender (although it still won't hit 90C), the MAF was changed last year, the injector loom was recently replaced, and I run with Millers through every tank. Am on Winter 15s (so one might allow that the stickier winter rubber will have an effect) and of course winter diesel is also formulated differently to prevent freezing, so that will be impacting, along with the aforementioned points about running with the heater/ screen demister/ lights on more. Maybe the return to warmer weather will help, but I think I will still go for the 5th gear mod in the coming months.
Black Pearl
Member
Hi Will, That's what I thought too. However on a recent trip. over to Skipton Auto's in fact, after an hour trip (50 to 60mph @around 2c) the webasto heater was still running.
The information from webasto says that modern direct inject diesels, do not generate enough heat to warm the engine sufficiently, when the temp is below 5c.
On my fathers car( a merc, a c220cdi) where the webasto has ceased, indeed in these tempretures the car never gets warm, even after 2 hours driving.
Webasto if anyone is interested can fit the A2 with a remote (Like an alarm kefob) or timer to switch the heater on before you get in the car. It's around £300 though!!!!
I did wonder about a simple switch to switch it off, in cold weather, and potentially increase MPG. But I figure that probably more MPG and damage will result as a consequence of running a colder engine. Not to mention a freezing cabin!
Nick
With it being such a cold winter i am leaving the 'auto' setting on all the time. previous winters i used to turn to 'econ' after the cabin got upto temperature. i am a 'post' webasto car with the electric(?) heating booster so the impact on economy will be different, albeit it must take some work by the alternator with a subsequent impact on the engine to keep up with the demand for power by the heater/battery. maybe this accounts for some of the adverse fuel consumption i am experiencing of late......
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Black Pearl
Member
I tend to use my Climate in the Auto and Econ at the same time. I guess this monitors the temp, but doesn't use the A/C?
I don't know if its possible to operate the webasto using the climate controls.
I didn't know that later cars had an electric heater. The Audi figures don't suggest that newer or earlier cars are any different. Except that early brouchures said they did 81mpg, and this later changed to seventy something!
I just completed four small journeys, 291 miles in total (about 20 were motorway the rest a mixture of potholed and not so potholed twisty back road and tolerable main road). I did this on 19.2 litres of diesel. Which is 291/4.223 mpg = 68.8 mpg
No DIS. I just filled up drove and filled up again. Im quite impressed actually as 60 of those miles were with 3 adults, 1 infant and the boot completely filled with logs. The rest were with 2 adults and an infant.
Tyres are 195/55/15 inflated to 34 psi front and 36psi rear. (a little hard!)
the total time driving was 7.2 hours so i guess that makes for an average speed of about 40mph which probably explains the mpg. That said I did drive fairly hard with a bit of dropping into third and flooring it to squeeze past some trucks. I certainly wasnt driving as conservatively as I could.
No DIS. I just filled up drove and filled up again. Im quite impressed actually as 60 of those miles were with 3 adults, 1 infant and the boot completely filled with logs. The rest were with 2 adults and an infant.
Tyres are 195/55/15 inflated to 34 psi front and 36psi rear. (a little hard!)
the total time driving was 7.2 hours so i guess that makes for an average speed of about 40mph which probably explains the mpg. That said I did drive fairly hard with a bit of dropping into third and flooring it to squeeze past some trucks. I certainly wasnt driving as conservatively as I could.
Today was the first proper warm day for me driving the car and what a difference it has made
Monday - 150 miles (temp ~5C)
Friday - 160 miles (temp ~15C)
average mpg = 76
If Monday mornings could be a bit warmer I could well hit 80mpg without beginning on mods like 5th gear and a remap.