i30 Owners Club

FUEL ISSUES & ECONOMY => DIESEL => Topic started by: THE i30 on January 01, 2013, 23:28:33

Title: CRDi fuel consumption
Post by: THE i30 on January 01, 2013, 23:28:33
Well my 2012 GD CRDi Manual now has 12,000km on it and I have noticed something unusual in the fuel consumption. I have tested this several times and keep getting the same results, I commute to work 5 days a week it's a 250km round trip 95% of it highway driving. If I set the cruise control at 100km/hr that's about 1900rpm in 6th gear it gets 4.4litres/km average for a tank of fuel, if I set the cruise control at 110km/hr that's about 2100rpm in 6th gear I get 4.1litres/km average for a tank of fuel. I use Caltex Vortex from the same service station all the time in fact it has never had any other type of fuel since new. I cant work out why it gets better fuel economy at a higher speed in the same gear, has anyone got any ideas why this would be so.
Title: Re: CRDi fuel consumption
Post by: ElleB on January 01, 2013, 23:37:10
Interesting....are the figures according to the on-board PC or are they verified by actual fuel used ..distance / fuel used on a brim to brim refill?

 Oh for a manual !!!   :mrgreen:

Cheers
  Elle B
Title: Re: CRDi fuel consumption
Post by: rustynutz on January 01, 2013, 23:44:47
I would suggest that perhaps at 1900rpm it's "labouring" a little so the "cruise" puts the "foot" down more for changes in road conditions such as hills. At 2100rpm the engine is spinning more freely so the electronic foot doesn't need to vary things as much.... :undecided:

Just guessing here so take what I say with a grain of salt... :lol:
Title: Re: CRDi fuel consumption
Post by: Doggie 1 on January 01, 2013, 23:48:52
 :whsaid:

I reckon that in the conditions and terrain you are driving in, 6th gear is more in the middle of the torque band at that speed and that if you were in 5th at the lower speed you would probably replicate the 4.1.
Just my thought.
Title: Re: CRDi fuel consumption
Post by: THE i30 on January 02, 2013, 00:21:52
Interesting....are the figures according to the on-board PC or are they verified by actual fuel used ..distance / fuel used on a brim to brim refill?

 Oh for a manual !!!   :mrgreen:

Cheers
  Elle B
That's the on-board I did the brim to brim thing early in the piece and was really impressed with the figures I'm pretty sure it was in the mid 4's so I didn't bother doing it anymore. I just fill it until it clicks off now and when I get to less distance to empty than my round trip I fill up again
Title: Re: CRDi fuel consumption
Post by: THE i30 on January 02, 2013, 00:27:55
I would suggest that perhaps at 1900rpm it's "labouring" a little so the "cruise" puts the "foot" down more for changes in road conditions such as hills. At 2100rpm the engine is spinning more freely so the electronic foot doesn't need to vary things as much.... :undecided:

Just guessing here so take what I say with a grain of salt... :lol:

Yeah I was thinking a bit along those lines also and seeing the speedo is out about 7km/hr at 100 it probably comes out at just over 100km/hr anyway so its all good. 
Title: Re: CRDi fuel consumption
Post by: rustynutz on January 02, 2013, 00:52:02
>seeing the speedo is out about 7km/hr at 100 it probably comes out at just over 100km/hr anyway so its all good.

That much?  :eek:
Title: Re: CRDi fuel consumption
Post by: THE i30 on January 02, 2013, 00:57:35
>seeing the speedo is out about 7km/hr at 100 it probably comes out at just over 100km/hr anyway so its all good.

That much?  :eek:

I checked it against a sat nav readout and it was saying 93km/hr and the cruise control was set at 100km/hr
Title: Re: CRDi fuel consumption
Post by: rustynutz on January 02, 2013, 01:00:33
I wonder if anyone else's GD speedo is out that much?  :undecided:

My speedo is out around 2kph, but that is in an FD....
Title: Re: CRDi fuel consumption
Post by: Phil №❶ on January 02, 2013, 01:02:55
I think Rusty / DB08 are on the money, although wind resistance  must be higher, we are only talking indicated 10 km / h or 6.2 MPH so I think that is offset for the reasons already stated. I assume your speedo is reading High, so is 100 actually 93 and 110 actually 103. I think that is a fair bit to be out IMO.  :undecided:

BTW I hope that's 4.4 & 4.1 / 100 kms  :whistler:
Title: Re: CRDi fuel consumption
Post by: THE i30 on January 02, 2013, 02:03:58
I think Rusty / DB08 are on the money, although wind resistance  must be higher, we are only talking indicated 10 km / h or 6.2 MPH so I think that is offset for the reasons already stated. I assume your speedo is reading High, so is 100 actually 93 and 110 actually 103. I think that is a fair bit to be out IMO.  :undecided:

BTW I hope that's 4.4 & 4.1 / 100 kms  :whistler:

Yeah that is per 100km
Title: Re: CRDi fuel consumption
Post by: Wittendorff on January 02, 2013, 11:17:01
I wonder if anyone else's GD speedo is out that much?  :undecided:

My speedo is out around 2kph, but that is in an FD....

Mine is, when the speedo says 90, the GPS says 84.
Title: Re: CRDi fuel consumption
Post by: AlanHo on January 02, 2013, 11:47:12
It is surprising how individual same spec cars behave so differently.

Coming back home yesterday from Cheltenham to Solihull along the M5 and M42 there is a 12 mile stretch of motorway I know well which is almost flat - according to my sat nav there is only a variation of 15 feet altitude between the lowest and highest points.

On reaching this section I reset the average fuel economy trip and drove gently at a steady 65 mph (105 km) in 6th gear (1900 rpm). It was a sunny day, no wind but cool at 8°C. Being new year's day there was very little traffic on the motorway and I had no need to overtake or change speed.  I did not use the cruise control.

At the end of the 12 miles section the trip showed an average economy of 69.2 mpg (4.08 l/100km).

I left the trip running until I reached home after a further 47 miles (76 km) of which 44 miles (71 km) were on motorways. This section of the motorway had occasional up and down slopes, the highest point reached being +430 feet . When I reached home at an elevation 280 feet higher than the start of the test, the trip was showing 59.6 mpg (4.74 l/100 km).
Title: Re: CRDi fuel consumption
Post by: Doggie 1 on January 02, 2013, 11:50:52
Which is right where mine is at at the moment.
Title: Re: CRDi fuel consumption
Post by: AlanHo on January 02, 2013, 12:08:53
Which is right where mine is at at the moment.

The problem I have Dave is that these figures are under the best conditions - no traffic, no proper hills, no side roads, no traffic lights or road junctions. Chuck a few of these into the mix - add a DPF regeneration every 200-300 miles and my true average comes down to 54.7 mpg (5.2 l/100 km) which is only 73% of the grossly misleading government combined figure of 74.3 mpg (3.8 l/100 km).

It is also way short of some outstanding economy figures claimed by other members.

You and I are obviously doing something very wrong.
Title: Re: CRDi fuel consumption
Post by: Doggie 1 on January 02, 2013, 12:29:47
I don't think we are, really.
I fuelled up this morning in a place called Mundaring.
I then drove to Midland which is at a lower altitude at which point my readout showed 2.9 l/100 kms.
I then drove to Karrinyup over near the ocean at which time it was up to 3.9.
By the time I got home through traffic (and up hill) it was up to 4.7.
So many variables, I guess.
Title: Re: CRDi fuel consumption
Post by: Wittendorff on January 02, 2013, 12:38:20
Since I started to brim it, I've done an average of 17,33 km/l.  This figure includes 800 km of motorway, three adults and luggage and 150 km/t on auto pilot, during which it averaged 14,69 l/km. Not so bad at all.
Personal record is 23,3 over 60 Km stretch, but that was so slow driving that even my wife complained  :Shocked:

When I start work again after the hollidays, I will try to experiment by NOT using the 6'th gear on higways IOT get some better usage of the torque.

I'm not complaining though as I've saved a little more than 300 euros on fuel in december only compared to my last car, a SAAB 9-3 SS Hirsch. Although it was quite funnier to drive.

/Jakob
Title: Re: CRDi fuel consumption
Post by: AlanHo on January 02, 2013, 15:01:13
Since I started to brim it, I've done an average of 17,33 L/km.  This figure includes 800 km of motorway, three adults and luggage and 150 km/t on auto pilot, during which it averaged 14,69 l/km. Not so bad at all.
Personal record is 23,3 over 60 Km stretch, but that was so slow driving that even my wife complained  :Shocked:

When I start work again after the hollidays, I will try to experiment by NOT using the 6'th gear on higways IOT get some better usage of the torque.

I'm not complaining though as I've saved a little more than 300 euros on fuel in december only compared to my last car, a SAAB 9-3 SS Hirsch. Although it was quite funnier to drive.

/Jakob

Jakob

Do you have your units mixed up. You can't possibly be using 17.33 litres per kilometer. At that rate you would use a full tank in just 3 km.

Perhaps you mean 17.33 km per litre which is equal to 5.8 l/100km or 48.7 mpg.
Title: Re: CRDi fuel consumption
Post by: Wittendorff on January 02, 2013, 18:35:37
Jakob

Do you have your units mixed up. You can't possibly be using 17.33 litres per kilometer. At that rate you would use a full tank in just 3 km.

Perhaps you mean 17.33 km per litre which is equal to 5.8 l/100km or 48.7 mpg.

You are completely right, I mixed it up, have though corrected it. Thanx for noticing.
Title: Re: CRDi fuel consumption
Post by: Asterix on January 02, 2013, 19:51:02
Well my 2012 GD CRDi Manual now has 12,000km on it and I have noticed something unusual in the fuel consumption. I have tested this several times and keep getting the same results, I commute to work 5 days a week it's a 250km round trip 95% of it highway driving. If I set the cruise control at 100km/hr that's about 1900rpm in 6th gear it gets 4.4litres/km average for a tank of fuel, if I set the cruise control at 110km/hr that's about 2100rpm in 6th gear I get 4.1litres/km average for a tank of fuel. I use Caltex Vortex from the same service station all the time in fact it has never had any other type of fuel since new. I cant work out why it gets better fuel economy at a higher speed in the same gear, has anyone got any ideas why this would be so.

That is quite fine figures.. :goodjob2:

Have you tried 100 km/h in 5th gear.. :question:  Could be interesting.
Title: Re: CRDi fuel consumption
Post by: ElleB on January 05, 2013, 06:48:05
Just returned last night from a trip north. did 799 clicks yesterday, 95 % was Pacific Hwy and we sat on 100-110 all the way, mostly with CC on, to give the foot and ankle a rest.... :wink:

 The wife topped up today brim to brim.. so that we didnt spoil the figures by the running around part of daily life and we got 50.4 MPG. for the trip home. Need to allow a slight variation as the speedo reads 2 KPH high compared to the Sat Nav..but all in all, for the auto that is fine... :happydance:

Now I need to do the 80K service and oil change... :sweating:

 BTW, the Mastercraft tyres are still running fine.. 21,000 on them now and nairey an mark to be seen, and quite too, hardly any road noise on the freeway.. running at ~ 37 psi.

When I had the tyres rotated  at the 20,000KM mark, they checked the wheel alignment and it did not need touching...  so just the cost of the tyre rotation and balance check.

 I really think that the camber kit has made life that much better also, oh and avoidence of the odd pothole not doubt helps. :rofl:

Title: Re: CRDi fuel consumption
Post by: Doggie 1 on January 05, 2013, 07:20:27
What's that in Australian?  :undecided:
It's amazing, I always used to think in mpg but now I can't.
Title: Re: CRDi fuel consumption
Post by: Phil №❶ on January 05, 2013, 07:24:16
5.6
Title: Re: CRDi fuel consumption
Post by: Doggie 1 on January 05, 2013, 07:26:03
Thanks Phil.
Saved me pulling my Elsimate out.
Title: Re: CRDi fuel consumption
Post by: Dazzler on January 05, 2013, 07:31:06
5.6

That's pretty very good Tony for an Auto  :eek: :goodjob:
Title: Re: CRDi fuel consumption
Post by: ElleB on January 05, 2013, 09:20:33
Sorry about the MPG,  when you drive a 1935 Dodge with a 7" speedo in MPH, one thinks in that same  unit..  :snigger:
To me a MPG figure is more meaningful than Lts /100km... but I guess it is just a matter of getting ones mind around it..  must be "old school"   :winker:

OH   I need to add that we are running a Spider black box, 2 notches up from zero setting.

 Cheers
 
Title: Re: CRDi fuel consumption
Post by: Doggie 1 on January 05, 2013, 09:21:58
 :lol:  No worries, thanks.
Like I said, I used to think imperially all the time but now I've been metricated.  :undecided:
Title: Re: CRDi fuel consumption
Post by: Dazzler on January 05, 2013, 10:40:36
:lol:  No worries, thanks.
Like I said, I used to think imperially all the time but now I've been metricated.  :undecided:

and sometimes castigated  :D
Title: Re: CRDi fuel consumption
Post by: Doggie 1 on January 05, 2013, 10:49:43
:lol:  No worries, thanks.
Like I said, I used to think imperially all the time but now I've been metricated.  :undecided:

and sometimes castigated  :D

But never castrated.  :)
Title: Re: CRDi fuel consumption
Post by: THE i30 on January 07, 2013, 00:55:58
I think Rusty / DB08 are on the money, although wind resistance  must be higher, we are only talking indicated 10 km / h or 6.2 MPH so I think that is offset for the reasons already stated. I assume your speedo is reading High, so is 100 actually 93 and 110 actually 103. I think that is a fair bit to be out IMO.  :undecided:

BTW I hope that's 4.4 & 4.1 / 100 kms  :whistler:

Ok a couple more tests I have done. Same piece of road same tank of fuel 100km of highway reset average l/100km and cruise control at same point.  100km/hr 6th gear 1900rpm 4.1L/100km, 100km/hr 5th gear 2300rpm 3.9L/100km and 110km/hr 6th gear 2100rpm 3.8L/100km. Very interesting figures  so it seems 2100rpm is the sweet spot and I think the extra 10km/hr must help when coming to a hill.
Title: Re: CRDi fuel consumption
Post by: Phil №❶ on January 07, 2013, 01:56:44
That sounds logical @ thanks for testing & sharing.  :goodjob2:
Title: Re: CRDi fuel consumption
Post by: alexeiw123 on January 07, 2013, 02:53:16
just though I'd throw in, very similair figures to what I'm seeing. 110km/h highway usage is roughly 4.1l/100

seems to be mid to low 5's for stop start driving.

got 1100km from a brimmed tank with about 70% highway.

I log all my k's and fuel with the android app 'acar' so I've got a tonne of statistics at my disposal, and also for the getz, and my old liberty GT. running costs are pretty much halved from the subaru.

The instantaneous economy readout has me driving like such a nana.
Title: Re: CRDi fuel consumption
Post by: Phil №❶ on January 07, 2013, 03:09:06
The instantaneous economy readout has me driving like such a nana.

At your age too.  :rofl: :rofl: :rofl:

That's good info  :goodjob2:
Title: Re: CRDi fuel consumption
Post by: alexeiw123 on January 07, 2013, 03:18:44
The instantaneous economy readout has me driving like such a nana.

At your age too.  :rofl: :rofl: :rofl:

That's good info  :goodjob2:

don't laugh, you should have seen my mates faces when I said I was getting a diesel hatchback! Kind of strays from the previous selection of cars.

No regrets yet :)
Title: Re: CRDi fuel consumption
Post by: THE i30 on January 07, 2013, 03:21:12
I wonder if anyone else's GD speedo is out that much?  :undecided:

My speedo is out around 2kph, but that is in an FD....

Mine is, when the speedo says 90, the GPS says 84.

Sounds like a good excuse to go to larger tyres and rims when I wear the originals out I reckon :)

Title: Re: CRDi fuel consumption
Post by: Phil №❶ on January 07, 2013, 03:30:09
The instantaneous economy readout has me driving like such a nana.

At your age too.  :rofl: :rofl: :rofl:

That's good info  :goodjob2:

don't laugh, you should have seen my mates faces when I said I was getting a diesel hatchback! Kind of strays from the previous selection of cars.

No regrets yet :)

Maybe one of them may see the light too.

Excellent  :happydance:
Title: Re: CRDi fuel consumption
Post by: Doggie 1 on January 07, 2013, 05:30:08
Very interesting and great fuel economy results.
Title: Re: CRDi fuel consumption
Post by: Lakes on January 07, 2013, 09:31:47


The instantaneous economy readout has me driving like such a nana.
[/quote]

That's great!, has the new GD Crdi trip PC got instant fuel useage readout?

Title: Re: CRDi fuel consumption
Post by: Doggie 1 on January 07, 2013, 09:34:01


The instantaneous economy readout has me driving like such a nana.

That's great!, has the new GD Crdi trip PC got instant fuel useage readout?
[/quote]

Yes, but in the form of a pretty useless strip readout that tells you very little.
Title: Re: CRDi fuel consumption
Post by: Lakes on January 07, 2013, 09:39:14
old friend of mine, thats always liked performance V8's ( still has some too ) three  years back he got his wife a new Focus Turbo Diesel manual after watching me, then riding in my i30 CRDi, but they thought the focus was nicer inside so got that. did about 250,000k in three years & today they just ordered another new Focus, i mentioned all the standard features on the new top of the line i30 he looked surprised. they wanted manual but Ford only use auto in diesel now.think DSG trans.
he gets it next week.
Title: Re: CRDi fuel consumption
Post by: Lakes on January 07, 2013, 09:42:00


The instantaneous economy readout has me driving like such a nana.

That's great!, has the new GD Crdi trip PC got instant fuel useage readout?

Yes, but in the form of a pretty useless strip readout that tells you very little.
[/quote]

will have to go have another look, but my i30 trip PC does not tell that much. but the new u2 now it has 34,000k up seems to perform well faster off lights than the old 5 speed i had too i like it.
Title: Re: CRDi fuel consumption
Post by: AlanHo on January 07, 2013, 10:06:11
As I have reported before - in the UK the instant trip recoder - a horizontal bar with no graduations - has the range O to 50 mpg (5.7 l/100 km). Totally useless in everyday use - unless you are climbing a steep hill fully loaded and pulling a 1 ton trailer.

I complained to Hyundai at the launch of the car and they told me a patch would be issued in June 2012 to correct the problem. It was not released so I complained again. They then informed me that they would not be patching existing vehicles - but cars built after September 2012 would have an amended instant trip scale so that it could display realistic figures.
Title: Re: CRDi fuel consumption
Post by: Doggie 1 on January 07, 2013, 10:23:56
The one in Australia is from 0 to 50 l/100 kms so a bit more realistic, but still as useless, really, as it's not calibrated in any way.
It's just a line.
Title: Re: CRDi fuel consumption
Post by: alexeiw123 on January 07, 2013, 11:30:09
Agreed. Its really impossible to know what economy your on, other than, roughly around about 5ish, give or take. But even still.. I find myself trying to keep it low
Title: Re: CRDi fuel consumption
Post by: constipated on January 07, 2013, 11:40:42
Ok a couple more tests I have done. Same piece of road same tank of fuel 100km of highway reset average l/100km and cruise control at same point.  100km/hr 6th gear 1900rpm 4.1L/100km, 100km/hr 5th gear 2300rpm 3.9L/100km and 110km/hr 6th gear 2100rpm 3.8L/100km. Very interesting figures  so it seems 2100rpm is the sweet spot and I think the extra 10km/hr must help when coming to a hill.

Confirms my suspicions that 1500-1700rpm is probably below the sweet spot for the engine. Perhaps turbo not on boost and assisting. That's why even at 100km in the GD, the optimal fuel economy is 5th gear, not 6th.

Things are a bit lower geared in the FD, so I think 1900rpm or so is the sweet spot which corresponds to about 90km/hr in 6th.
Title: Re: CRDi fuel consumption
Post by: THE i30 on January 07, 2013, 22:30:00
Ok a couple more tests I have done. Same piece of road same tank of fuel 100km of highway reset average l/100km and cruise control at same point.  100km/hr 6th gear 1900rpm 4.1L/100km, 100km/hr 5th gear 2300rpm 3.9L/100km and 110km/hr 6th gear 2100rpm 3.8L/100km. Very interesting figures  so it seems 2100rpm is the sweet spot and I think the extra 10km/hr must help when coming to a hill.

Confirms my suspicions that 1500-1700rpm is probably below the sweet spot for the engine. Perhaps turbo not on boost and assisting. That's why even at 100km in the GD, the optimal fuel economy is 5th gear, not 6th.

Things are a bit lower geared in the FD, so I think 1900rpm or so is the sweet spot which corresponds to about 90km/hr in 6th.

I like the idea of being able to do 110km/hr in 6th gear and getting better economy than doing 100km/hr in either 5th or 6th gear :)
Title: Re: CRDi fuel consumption
Post by: alexeiw123 on January 07, 2013, 22:32:01
the confusing part is that on the dash screen, there is an indicator that tells you which gear to be in for best economy, and it will start recommending 6th gear at anything above about 65km/h which I feel is true for coasting along, but I always shift down before starting to climb at those speeds, even though the torque can easily pull you up a slight incline in 6th at those speeds.
Title: Re: CRDi fuel consumption
Post by: THE i30 on January 07, 2013, 22:35:38
the confusing part is that on the dash screen, there is an indicator that tells you which gear to be in for best economy, and it will start recommending 6th gear at anything above about 65km/h which I feel is true for coasting along, but I always shift down before starting to climb at those speeds, even though the torque can easily pull you up a slight incline in 6th at those speeds.

I turned mine off its so annoying flashing at you all the time
Title: Re: CRDi fuel consumption
Post by: Doggie 1 on January 07, 2013, 23:21:18
I generally don't do 6th until 80 km/h.
In fact I don't think mine tells me to shift until about then anyway.
Title: Re: CRDi fuel consumption
Post by: rustynutz on January 08, 2013, 02:06:10
:
Yes, but in the form of a pretty useless strip readout that tells you very little.

I turned mine off its so annoying flashing at you all the time

I'd rather they didn't fit these "useful" aid's than to do a half arsed job like they appear to have done in the GD.....   :fum:
But really, do we really need to be told when it's time to change gear?  :rolleyes:
I find it all just a big wank....
Title: Re: CRDi fuel consumption
Post by: alexeiw123 on January 08, 2013, 02:58:40
no we don't need to be told, and yes it is a wank.

I find the gear indicator is a good nudge in the ribs when other people drive my car that are used to higher revving smaller cars, other than that.. useless, but I don't find it so in your face that you can't ignore it.

I would much rather have a freaking digital clock on the dash though, rather than on the nav screen (sometimes)
Title: Re: CRDi fuel consumption
Post by: Doggie 1 on January 08, 2013, 04:17:29
It doesn't worry me it being there at all.
I think it is intended as a fuel saver and encouragement to drive economically but it tends to want you to change up earlier than I otherwise would.
I just continue to drive by my own intuition. I'm not going to labour a car in 6th gear because an electronic gadget tells me to, but as I said, it doesn't bother me that it's there.
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