GTTDI economy Drive Vic/SA

[STV4SYT]

OK, today i set out on an road trip to test out the economy of the golf (amongst other things) had some very weird findings.

Usually from my house to Geelong the onboard computer is at around 4.0 l/100 thats with 2 adults and some luggage on board. Today, just me, small overnight bag with laptop and an esky wth 12 beers in it (and ice from warnambool).

To Geelong got 4.8l/100, once i cleared Geelong it had dropped to 5.1 and gradually along the way got down to 5.4l where it stayed for the majority of the trip. last big trip i did to Port Fairy and back i averaged 4.6 for the entire journey (including some hooning along GOR)

2 things spring to mind here,

1 its very windy today, ive been driving into it and the car is getting blown around a lot. but is it going to cause me to use an extra litre for every 100km?

2. car has just shy of 11,000km on it and i didnt do the 7,500 service, is it now getting upset at me?


Ive not driven any differently to normal, on the speed limit (or thereabouts). Occasionally overtaking roadblocks (so accelerate from 80/90 -140ish) maybe a dozen times.

some figures.

total distance travelled 487km 460km left

86km/h average and 5.4l/100 in 5h 40minutes. This does include some mucking about in Mt Gambier to get a coffee and try to get some wifi, plus the obligatory drive up to the blue lake.

I should just about make it home on that as to the border i had 5h 5m 454km and 560 km left in the tank.

Hopefully tomorrow with an empty esky (which is pretty heavy) it will do better.

[gregozedobe]

Sounds like you are believing your MFD ? Mine are both notoriously inaccurate, variable and always optimistic. The only way to be accurate is to calculate from fill to fill, and average over at least 3 fills (to allow for the odd "under-fill").

Aircon can use a bit extra, as can side-headwinds. Another possibility is a fill of low quality fuel. Every cold start gives a hit of fuel consumption. Did you check your tyre pressures before you left ?

"Old" oil in the engine is not likely to cause a big increase in fuel usage (it may increase engine wear if you go for too long though - up to 15,000 of highway usage sounds OK to me)

The answer may lie in more than one of the above.

[STV4SYT]

Sounds like you are believing your MFD ?

- Im not, but its usually consistently inaccurate, as in same trip, same circumstances, MFD gives same reading. for the record, i had a consistent 4.1 from the airport to home last monday, which is what i usually get, and i do that run at least once a fortnight.

Aircon can use a bit extra, as can side-headwinds. Another possibility is a fill of low quality fuel. Every cold start gives a hit of fuel consumption. Did you check your tyre pressures before you left ?

Aircon was off most of the way, and tyre pressures were checked yesterday when i filled up to be around 34psi.

"Old" oil in the engine is not likely to cause a big increase in fuel usage (it may increase engine wear if you go for too long though - up to 15,000 of highway usage sounds OK to me)

Thats what i figured too, must be the wind.

[WEDEL.1]

[QUOTE=steve_tdi;2312892. car has just shy of 11,000km on it and i didnt do the 7,500 service, is it now getting upset at me?[/QUOTE]

My Dealer told me (and the books) the first service is at 15,000 or 12 months, and not to do anything until then.

Maris

[Guest212]

Sounds like you are believing your MFD ? Mine are both notoriously inaccurate, variable and always optimistic. .

according to the receipts, mine is pretty much spot on.

but my speed isnt.

[POLARBEAR666]

No need to worry about over / under fill.

Its simple.

Reset trip meter.

Drive till empty.

Fill car up and note the L it took to fill the tank. So say 51.3L

Check trip meter = 630km

Now do the math 51.3/6.3=8.14l/100k

That's exact. Its a pure measure of your fuel use over the distance you traveled and it ignores over under filling issues.

[STV4SYT]

No need to worry about over / under fill.

Its simple.

Reset trip meter.

Drive till empty.

Fill car up and note the L it took to fill the tank. So say 51.3L

Check trip meter = 630km

Now do the math 51.3/6.3=8.14l/100k

That's exact. Its a pure measure of your fuel use over the distance you traveled and it ignores over under filling issues.

I do this anyway too, but i know that going by the information i have available to me now that the car is consuming a reasonable amount of fuel more than normal and am trying to get the bottom of it.

ill fill it when i get back to melbourne.

[jets]

I would say the prevailing winds has a lot to do with it. When I travel in an easterly direction[from Adelaide to Melbourne] I always get better economy than on the return trip. It is even more noticeable when towing. I can always remember travelling to Mildura from Adelaide in my diesel Toyota Forerunner with a tail wind & achieving 39mpg. The caravan experts always say, if you are doing a round trip around Aust, to travel in an anticlockwise direction to take advantage of the prevailing winds.

[Russ59]

I'm getting on average around 6.2 L/100 k's with a combination of city / hwy driving, spirited at times. I couldn't be happier with this especially considering the amount of power on hand to go with it. I only have around 4,500 k's on the clock and it is consistently giving me excellent fuel economy figures IMO. The specs on the TDI GT Sport have it down at 6.6 L / 100 for manual trans. and 6.8 L / 100 for the DSG. I consider anything less is a bonus, the fuel consumption figures that VW have claimed are certainly a lot more attainable and true than the figures that Ford claimed for the BA XR6 Falcon I traded. I know the Falcon is a totally different car but the fuel consumption figures were claimed @ 7.4 L / 100 highway and 11.5 L / 100 city. The best I managed driving very conservatively from the NSW South Coast where I live to Canberra approx. 3 hrs drive and 99% freeway (fine weather) was 10.2 L / 100, this was on a well maintained low k's engine. Not even close to the claimed figure !!!

Russ

[stark27]

No need to worry about over / under fill.

Its simple.

Reset trip meter.

Drive till empty.

Fill car up and note the L it took to fill the tank. So say 51.3L

Check trip meter = 630km

Now do the math 51.3/6.3=8.14l/100k

That's exact. Its a pure measure of your fuel use over the distance you traveled and it ignores over under filling issues.

Same method I use and is way more accurate then my MFD would have me believe. My MFD would read anywhere between 5.1 and 5.6, my actual calculated using above method is 6.0-6.3.

It's simple but works brilliantly.

[gregozedobe]

No need to worry about over / under fill.

Its simple.

Reset trip meter.

Drive till empty.

Fill car up and note the L it took to fill the tank. So say 51.3L

Check trip meter = 630km

Now do the math 51.3/6.3=8.14l/100k

That's exact. Its a pure measure of your fuel use over the distance you traveled and it ignores over under filling issues.

It is only exact IF you fill to precisely the same point every time. If you haven't got a mark on the filler tube then it is very unlikely you always fill to the exact same point every time.

I know that with the usual diesel froth and occassional filler pipe "burps" and varying levels of patience when I'm filling up my TDI that I can sometimes put anything up to 2 litres more or less each time I fill. That is why I said it is better to average over 2 or 3 fills to eliminate over or under fills.

If you ALWAYS take 10 minutes or so to let the froth settle and keep putting in a little bit at a time until you see clear (froth free) diesel at the top of your filler pipe then you will be getting an exact figure, if you don't then I very much doubt it. I know I'm more patient than most people, and I'm not that patient Plus the last time I tried to, the auto shut-off wasn't quite sensitive enough and I got diesel all down the side of my van - I'm not doing that again

[STV4SYT]

Well im back

Didn't quite make it to melbourne on 1 tank, but got very close.

Ended up with the km til empty indicator going to 0 at about 903km, just as i was leaving Geelong. i did another 8km to the Little River servo and filled it up.

53.96l !!! not much to go if its got a 55l tank.

Economy returned by calculating was 5.91 l/100km

at the time MFD said 5.5

By the time i got back to melb it had dropped on the MFD to 5.3

Todays Figures

Mt Gambier to Melb, via Hamilton, Mortlake, Geelong

445km, 4h 56m, 90km/h average speed @ 5.3 l/100


Total for the 2 days round trip (including touristy stuff over there)

967km, 11h 35, 83km/h @5.4l/100

Not too bad really, had hoped to get over 1000 as last time i tried i got 947 with more weight in the car.

Definitely the way to go is the way i came back - going there thru warnambool was 472km and took about 5h 20m

Was driving "moderately" as in needle on 110 (103 actual) the whole way where permitted and accelerating hard past anything that got in my way.

[BeigeJet]

Well im back

Total for the 2 days round trip (including touristy stuff over there)

967km, 11h 35, 83km/h @5.4l/100

Hi Steve,

I'd love to be able to get a photo of my MFD display from the Jetta after a trip away during the recent school holidays.

4,300 km average at 89 kmh and 5.1 lt per 100!

Strangely enough the economy on this trip was accurate when using the actual litres filled and actual distance. Normally the MFD is optimistic by about 0.3 lt per 100.

I've been keeping detailed records since new (yes I'm anal but also want to keep tabs on my lease provider!) and for life of car so far got 6.07 lt per 100 based on fuel filled and 54,227 km.

I've noticed too that head winds do play a part. Two identical trips to the Blue Mtns in NSW from Melb, same rote, same distance, same time of day, similar load of 3 adults and luggage, similar traffic but one southerly prevailing winds and one northerly prevailing and got 4.9 and 5.4 per 100 respectively.

[STV4SYT]

Ah, pictures....


I like this one fromm earlier.

[BeigeJet]

While driving with cruise!

Well done!

I'm impressed but constable Plod would not be! lol