[succulant]

I've just put my crdi in for its third year service and my average mpg has shot up from about 61 to 64mpg and in a trip last weekend to Inverness (from Ayrshire) I maxed out at 69.5mpg and averaged 64.5mpg overall over the 550 mile round trip. I thought the economy would be good when I bought the car just before last Christmas but this is fantastic. Long may it continue!

[Dazzler]

  I wonder what oil they put in? 

Expect a visit from Alanho.. He will take some convincing those figures are accurate 

[succulant]

Its all true. I do a lot of miles commuting and measure the mpg brim to brim myself.

[AlanHo]

Dazzler is right. If you really can prove your figures are absolutely correct - write to Hyundai head Office and give them the facts. They need to know about this and I am sure they would like to borrow your car for detailed analysis so they can learn from it.

I assume it is a bit hilly on the route you did - which makes your figures all the more remarkable. If your maths is correct - my guess is that either your odometer is wildly optimistic or when you brimmed the car you did not fill it absolutely to the brim each time. I know from my own experience that you can easily think the car is full - but wait 3 minutes for the foam to settle, give the car a nudge to shake it and you can get a further 6 or more litres in the tank.

Sorry to be so negative - but I would need a lot of pursuading that an i30 is capable of that economy over a long distance though hilly terrain unles you were to strip all the seats and trim out, empty the boot, chuck out the spare wheel, remove the wing mirrors, and drive naked to minimise weight and wind resistance. You would then have to drive with the lightest possible touch on the throttle using every fuel saving trick in the supermiling book.

[FatBoy]

Sorry Alan, I just went visual on you driving naked in your stripped out i30!!   

"Well Officer, I was trying to improve my mileage."

"I'm sure you were, Sir."


While I don't get the mileage that others claim to get in their cars (I'm not saying they don't get those figures, just that I don't), I am still extremely happy with my average of 5.6 l/100km, considering I used to drive a V8.

[AlanHo]

I talked at length to the Hyundai staff at the Silverstone venue about fuel economy of the 1.6 CRDi. They admitted that the official figures which manufacturers are required by UK law to publish - are the result of running the car on rollers, with no wind resistance, untypical weight, untypical rolling resistance, from a warm egnine start and with no acceleration inertia in laboratory conditions. They do not expect anyone to achieve these figures on public roads. They said their only value was to compare one cars theoretical economy with another.  They were of the opinion that my car's economy was about average for my mix of motorway and urban driving.

My car has averaged 48.6 mpg (5.8 L/100km) over 12,713 miles (20,450km) from new. I record every fill, always brim it and have allowed in the calculation for my odometer being exactly 2.5% under (as checked over a long distance against the motorway kilometer posts). The trip recorder tends to show a figure about 5% on average above the true consumption. I drive as frugally as possible and do about 70% long journeys averaging 60 mph on fast roads and motorways and about 30% urban.  I rarely do more than 70 mph - other than when over-taking.

On a separate post I reported that I have checked my economy on a dead flat road over 6 miles at 60 mph with varying road surfaces. I reported as follows :-

Today we drove up and back down this section of road and I took particular notice of the instant fuel consumption with the cruise set at 60 mph. The road was still slightly wet after some rain in the night, just my wife and I in the car, empty boot, and there was very little wind. It was a dull miserable day with a temperature of around 10 centigrade.

On the sections of road where there was old tarmac and road noise was at its highest the trip showed a fairly consistent 54.2 mpg [5.2 L/100 Km]
On a half mile section of concrete road the trip showed 55.7 mpg.[5.1 L/100 Km]
On the sections of road which had recently been resurfaced with the new low noise tarmac the trip showed 58.2 mpg.[4.9 L/100 Km]

This test involved no hills, no acceleration and no headwind. It is an indication of the absolute maximum my car can achieve under ideal public road conditions.  Hence my average to date of 48.6 mpg looks to be realistic.

Cynial I may be - but most people with the diesel i30 and equivalent KIA Ceed claim similar figures to mine. It is only a tiny minority who are blessed with cars so remarkable and untypical that they can claim average economy above 60 mpg (4.7L/100km)

[Ugly Mongrel]

Alan, you could lighten the load more if you took your teeth out, threw your specs out the window and went to the loo before leaving. Now there's a mental picture.

[AlanHo]

Alan, you could lighten the load more if you took your teeth out, threw your specs out the window and went to the loo before leaving. Now there's a mental picture.

It isn't me that is claiming very rare economy figures. I am only pointing out what someone would need to do to maximise them.

You could add to your list :-

Seek out every possible bump in the road to get the wheels airborne as often as possible to minimise rolling resistance.

Drive a couple of feet behind a large truck to get an aero tug

Fit the car with the notorious go-faster stripes and a chip-in-a-box

I'm having my worst economy result at the moment and it's because I've not done a trip or travelled on a highway of any sort for the current tank (750km so far). I also did a spot of furniture moving with a trailer but I only dragged that around for about 60km.

Even so, the trippy shows 5.4l/100km (52mpg) at an average of 45km/h (28mph).

Excepting when the car was new have I ever finished a tank in the fives. I once saw 3.9l/100km for a single weekend trip and usually see < 4.5 these days for a single tank.

That's 62+mpg not allowing for error but comparing trip meter to trip meter would seem fair even if the actual figures are rubbery.

Perhaps I am lucky or perhaps my running-in technique has paid off. However I do drive economically with a purpose.

Many of us here have related similar experience so I'm sure succulant's result will be repeatable - for him at least.

Implicit in his story was that the oil made a difference. I noted a significant and immediate change when switching oil also. A point worth noting.

@succulant
Nice economy. What oil did you put in?

Even tho trip computer average mpg can lie, distance to empty when you go to the last 50km in tank + travelled kilometers is very accurate.
1000+ km on tank normal for you?

[constipated]

I'm having my worst economy result at the moment and it's because I've not done a trip or travelled on a highway of any sort for the current tank (750km so far). I also did a spot of furniture moving with a trailer but I only dragged that around for about 60km.

Even so, the trippy shows 5.4l/100km (52mpg) at an average of 45km/h (28mph).

Maybe it's an indication of how bad Sydney traffic has gotten, or else other people's commute is so different to mine, but 3 days a week I drive 40km heavy suburban traffic one way to work, and 2 days a week 25km one way of 60-70km/hr roads, smooth run, against traffic. Yet I simply cannot get my average speed above about 37km/hr per tank.

I get around 5.8L/100km measured by brim to brim. Trip computer usually says 5.6 or so.

I can understand that people like Pip are getting much lower, but obviously our driving (Syd vs Melb traffic) is vastly different. It's obvious if a "slow" tank for you is average of 45km/hr.

I can understand that people like Pip are getting much lower, but obviously our driving (Syd vs Melb traffic) is vastly different. It's obvious if a "slow" tank for you is average of 45km/hr.

Frankly, the average surprised me too and probably, at least partly, explains why I have no trouble getting relatively good economy.

I also should let you know I seldom need to travel in commute traffic these days and having often (worked and) driven in Sydney, yes, it's much better here.

[succulant]

Its understandable that a few people are a bit dubious. I've owned several tdi's in the past and none have come close to 64mpg average but this is correct. Last week there were also two of us in the car and luggage. As for brimming the tank, I always fill it to the first click which is normally about 40ish litres, re-set the trip and let it run down to about an eighth of a tank. The journey was largely A and M roads at 60mph for most of it. I've attached a photo taken after about 100 miles of the trip showing 69mpg but it did go to 69.5 shortly afterwards. There aren't anymore photos as my exasperated girlfriend wouldn't take anymore. At the end of the journey I filled it up again and the average shown on the trip was pretty much bang on what my figures showed.

I'm not sure what type of oil was put in but it was serviced at the local Hyundai dealer so i guess its whatever grade its supposed to take. BTW the 3rd service was £215 inc mot and courtesy car - a surprisingly nippy i10 1.2 if anyone is interested.

[Phil №❶]

@ succulent

Unfortunately, filling to the 1st click is not an accurate fill. Much more fuel is able to be added after the 1st click, so this introduces possible calculation errors. THERE IS ONLY 1 WAY TO KNOW HOW MUCH FUEL WAS USED ON A TRIP AND THAT IS TO START THE TRIP WITH FUEL RESTING AT THE LIP OF THE FILLER PIPE, DRIVE THE TRIP AND REFUEL AT THE SAME PUMP TILL FUEL IS RESTING AT THE LIP OF THE FILLER PIPE AGAIN. We would all be interested to see your results if performed this way. 

[mjt57]

Yesterday the fuel light came on. About 15 kays or so later I filled it up. Again, to the first click it took 44l (always 43-44l).

And this is the second fill where I continued on to fill it "to the brim" which took a while due to the foaming action and settling. But as I did the first time I "brimmed" it, I filled it to where the neck starts to curve outwards.

And my phone app, Acar, tells me that this fill saw an average fuel economy of 6.5l/100km (dunno what it is to mpg). So, it's gotten worse since the last one (5.9).

Driving consist of a bit of commuting to work, which is a 20km round trip of about 4km of 60 km/h and the rest at 100 km/h or 80 km/h and little or no overtaking. Rest of the driving consisted of a long trip to a place called Sorrento in the bay area of Melbourne, a city in southern Australia, and one or two other long trips.

I got about 850km til I got to the low light, with DTE suggesting about 120 km to empty.

So, when I read these extraordinary claims of low 5s/high4s I have to wonder what I need to do to achieve this.

Whatever, the car is costing around $80 a month to run which isn't bad by anyone's standard.

[mjt57]

@ succulent

Unfortunately, filling to the 1st click is not an accurate fill.

I would dispute this.

While you can get a visual check on the actual level, if you're filling at the same bowser, as I do, each time, then the first click fill should be about the same each time.

As I've written in another thread on this topic, All of my fills have been to the first click until the last two, which I filled to the brim.

The "first clickers" were done shortly after the low fuel light came on. Each time it took 43-44l, depending on distance travelled since the low light. So, at least there is consistancy there.

And with the brimmer fills I always checked the amount to first click before continuing to fill. Again, 44l, as my Acar notes tell me.

Not sure what the relevance of speedo accuracy is, unless it's wildy inaccurate from fill to fill, which I doubt. As long as it's the same from fill to fill, then readings should be consistant, shouldn't they?

Whatever, since doing the brimmers, my fuel economy went from 5.9 in Acar, to 6.5l/100km...

Anyway, I've now finished with that particular experiment. I'll continue to fill to the first click, mainly because it saves on time at the bowser and not being covered in fuel when it burped and blew back some onto me yesterday...

[Phil №❶]

With 120k's dte + your travel, that would be nearly 1k to the tank which is good. How would you describe your driving technique. Some people drive for economy (me), and others to keep up with traffic or have fun (sporty). Naturally, this will affect your economy. I'm fairly certain that I can get that figure from ours, yet it is an auto, so maybe you need to tread lightly on the go pedal.

[AlanHo]

I am interested to see someone else with my average mileage. The mystery deepens.

[asathorny]

I am interested to see someone else with my average mileage. The mystery deepens.

I have similar, actually slightly LESS milage than you Alan and most of my driving is on the M way's.  HOwever when I am round town I am a heavy footed bugger away from the light :-(...   I average but 44 in a 1.6 petrol Edition.   I am OK'ish with that.     

I did used to get 67 to the gallon back in the day, when I was twenty one and whizzing round on my Lambretta, never go it in a car tho.

Not saying that I don't believe what this young mans telling us I have no way of testing his claim, I would however say that relying in the dash board dislay is a  bit iffy

My twopennyworth

[AlanHo]

I would consider an average of 44 mpg in a 1.6 petrol car to be pretty good. My last car - a 2 litre Audi - struggled to get over 37 mpg on long runs and averaged 33.6 mpg over my 23,00 mile, 2 years ownership

[succulant]

I agree with mjt57. I fail to see what relevance filling to the neck makes to the overall average mileage. I fill to the first click and run down to an eighth every time before refueling about another 40 litres therefore that gives consistency. Its never been slightly different never mind wildly different. If i filled to the neck all that would happen would be that my total mileage for the tank would increase but i suspect the average mpg would be the same or ever so slightly lower to take into consideration the additional weight of the extra fuel. According to my maths the onboard trip is usually quite accurate although it has underestimated once showing 58mpg when it actually did 61 overall for the 40litres I put in.

I am an economical driver. I try to stick to under 2000 revs when accelerating and 60mph whenever possible only going above that to overtake. I live in a rural location and work shifts so the roads are generally quite when I'm commuting therefore about 23 of my 25 mile commute is at 60mph and I rarely get caught up in stop-start traffic. The car is also a manual 'box and I don;t have cruise control. Its pretty much ideal driving conditions for good economy.

We have two cars so in the interests of accuracy I will do a short circuit in our other car (an ancient Rover tdi that refuses to die) to see if the trip mileage shows the same distance.

By the way, 847563 I think you need a new keyboard as your caps lock key seems to be sticking...

[Phil №❶]

There's nothing wrong with my keyboard, caps lock was intentional.

I have to disagree with the fill to 1st click mentality. If you use that method, all you can say is my car is reasonably economical, based on a close, but approximate fill quantity. 'There is an accurate way to do it which has been explained to you. If you choose to use the other method, then so be it.

If you choose to use the other method, then so be it.

I think both points of view have been put.

I've tried all methods including using the trip computer and just simply seeing how far a tank does. They all roughly correlate to the extent that I reckon whatever method has been used, the results for that particular car/driver/conditions will be accurate enough to compare with each other.

Why they differ for reasons other than the measurement technique is more of interest to me. The three variables I mentioned, car, driver, conditions, I suspect hold the answer.

But which is it? More likely the last two than the first IMO. Swap cars same result. Lakes has done that and from his posts it looks like the driver is the greatest influence. With apologies to Alan.

[mjt57]

There's nothing wrong with my keyboard, caps lock was intentional.

I have to disagree with the fill to 1st click mentality. If you use that method, all you can say is my car is reasonably economical, based on a close, but approximate fill quantity.

It depends on the bowser, I s'pose, as to the accuracy or otherwise of each fill. I use the same one all the time, and each time, without fail it clicks off at 43l, or maybe 44l if I've travelled any distance after the low fuel light comes on.

And your description of this point of view makes it sound like it's something to be avoided, too. Not sure but I'd say that you've having a go at us "first clickers"...

[markdyer72]

well i havent quite used a full tank yet, but the trip is averaging 50.4MPG at the moment, i like many others on here always fill to the first click and then carry on until i have a nice round pound figure to pay , i also use torque to calculate the MPG and when i fill up next will compare those results to the trip....  i generally on average do 200 - 250 miles per week, 4 days outta 5 my commute to work is probs no more than 11 miles also i travel 30 miles to work at least 1 day per week

[mjt57]

I've just put my crdi in for its third year service and my average mpg has shot up from about 61 to 64mpg and in a trip last weekend to Inverness (from Ayrshire) I maxed out at 69.5mpg and averaged 64.5mpg overall over the 550 mile round trip. I thought the economy would be good when I bought the car just before last Christmas but this is fantastic. Long may it continue!

Hyundai's fuel economy claim based on Australian Standards is 4.5l/100 km.

Your figures converted:
61 mpg - 4.6l/100km
64 mpg - 4.4l/100km
69.5 mpg - 4l/100km

Mine:
Average: 5.9l/100km - 47 mpg
Worst: 6.4l/100km - 44 mpg
Best: 5.5l/100km - 51 mpg

I have been driving normally, a bit hard and like a pussy.

I drive on open freeways, a short 60/80/100/80/100/60 km/h 20km round trip to work 4 days out of every 10.

I last filled up on 10th of Feb, covered 900km to fill up on 3rd March. I don't rev it past 4,000rpm and tend to "grunt" it using lower gears and short shifting, rather than to rev it out, but I don't labor it.

The car's also only done about 5,200km all up. So maybe it will improve. But my Android phone app, Acar, tells me that fuel consumption hasn't changed much since the first fill, except for the last one which averaged the 6.5l/100km.

Maybe you should give Jeremy Clarkson a call, see if he wants to do a segment on economical driving (fat chance, given what those clowns like doing).

[rustynutz]

I don't rev it past 4,000rpm and tend to "grunt" it using lower gears and short shifting, rather than to rev it out, but I don't labor it.

Me thinks there's your problem, Martin.....
I suspect you're still driving it too much like your old petrol car. 4000rpm is still reving it out, in my opinion.
Try limiting your revs to no more than 3000rpm (or less) and I'm sure your fuel economy will improve.... 

[AlanHo]

In a separate thread I reported on testing my car over a flat 6 mile (10km)  length of road at a steady 60 mph (97 km/h) using the cruise control to eradicate driver influence.  I have subsequently done several similar tests without cruise and achieved similar results.

https://www.i30ownersclub.com/forum/index.php?topic=12687.0

This proved that the best economy my car was capable of was 58 mpg (4.9 L/100km) in ideal conditions at 60 mph. 

During this test I did not accelerate or brake and I stayed in 6th gear . I cannot see how it can be argued that any other driver in that car seat, at that time, would do any better or worse.  Hence I do not consider that my driving style is a major contributor to the poor economy of my car compared with some others. In fact – when I was a member of a local Audi Owners Club - I came 3rd and 2nd out of approx. 30 drivers in the two 100 mile economy competitions we ran on our fun Sundays. Of necessity the results were evaluated by trip recorder readings for the specific country roads journey over which we had to average 45 mph.  Hence I have some experience of driving frugally.

The current statistics for my i30 1.6 CRDi 6 speed manual car are :-
Best fill                                              55.28 mpg (5.1 L/100km)
Worst fill                                            42.25 mpg (6.7 L/100km)
Average to date over 13000 miles        48.92 mpg (5.8 L/100km)
These figures take account of a 2.5% odometer error on my car.

A previous car – an Audi 2.0 TDi 5 speed manual produced the following statistics – but driven more spiritedly than I drive the i30 :-
Best fill                                               52.3 mpg (5.4 L/100km)
Worst fill                                             43.32 mpg (6.5 L/100km)
Average over 38600 miles                    47.13 mpg (6.0 L/100km)

For some years, for each car I have owned, I have kept a spreadsheet which records every fill and the calculated mpg statistics. I have always brimmed the tank to the lip and with diesel cars allowed plenty of time for the foam to settle.

Perhaps the most remarkable car I have owned was an Audi 1.8 Turbo petrol A6 which on a long run would average 48 mpg. I owned this car for 2 years and over 26,700 miles it averaged 38.1 mpg (7.4 L/100km) despite having great performance which I used from time to time. 

This proved that the best economy my car was capable of was 58 mpg (4.9 L/100km) in ideal conditions at 60 mph. 

Alan, this is about what I get at a steady 100kmh also. I think the difference is what you do (or are forced to do by the conditions) for the rest of the drive.

[succulant]

I've just put my crdi in for its third year service and my average mpg has shot up from about 61 to 64mpg and in a trip last weekend to Inverness (from Ayrshire) I maxed out at 69.5mpg and averaged 64.5mpg overall over the 550 mile round trip. I thought the economy would be good when I bought the car just before last Christmas but this is fantastic. Long may it continue!

Hyundai's fuel economy claim based on Australian Standards is 4.5l/100 km.

Your figures converted:
61 mpg - 4.6l/100km
64 mpg - 4.4l/100km
69.5 mpg - 4l/100km

Mine:
Average: 5.9l/100km - 47 mpg
Worst: 6.4l/100km - 44 mpg
Best: 5.5l/100km - 51 mpg

I have been driving normally, a bit hard and like a pussy.

I drive on open freeways, a short 60/80/100/80/100/60 km/h 20km round trip to work 4 days out of every 10.

I last filled up on 10th of Feb, covered 900km to fill up on 3rd March. I don't rev it past 4,000rpm and tend to "grunt" it using lower gears and short shifting, rather than to rev it out, but I don't labor it.

The car's also only done about 5,200km all up. So maybe it will improve. But my Android phone app, Acar, tells me that fuel consumption hasn't changed much since the first fill, except for the last one which averaged the 6.5l/100km.

Maybe you should give Jeremy Clarkson a call, see if he wants to do a segment on economical driving (fat chance, given what those clowns like doing).

I don't think 115bhp is enough power for that doughnut to be interested lol