[AlanHo]

My i30 1.6 CRDi has done 10975 miles (17,662 Km) and used 227.84 galls (1036 litres) of diesel from new which works out at an average of 48.16 mpg (5.9 L/100Km). Brim to brim calculations generally align with the trip computer – which I reset at each fill-up.

Checking my odometer against motorway 1 kilometre distance posts over long journeys has proved that my odometer is reading 2.5% slow – hence the car has actually done 2.5% more miles than indicated. If so – the actual year-to-date fuel consumption is 49.4 mpg (5.7 L/100 Km).

The best brim to brim economy I have ever achieved on a 450 mile run averaging 62 mph (99 Km/h) was 53.4 mpg (5.3 L/100 km) – the trip computer showed 53.9 mpg for the journey which is very close. I guess the car has spent about 60% of its life on motorways and 40% on mixed urban roads.

I am not a hard driver and drive with a light foot with tyres at 36 psi.  Hence I am disappointed with the economy of my car – mainly because many members of this forum claim much better results. I recall one member recently claiming to average 63.5 mpg (4.4 L/100 Km).

I complained to the dealership at the recent first service about poor economy – but they considered it to be acceptable. At my insistence they checked for any problems with the car – but drew a blank.

My first question is that my car is fitted with a DPF – but I have never seen any indication that it has regenerated. Is this normal and could this be a factor in poor fuel economy?

My second question is whether my i30 car has a Eolys fluid tank. A friend with a 2009 Ford Focus 1.6 TDCI – but who does much bigger mileage than me - complained of a significant drop in economy with his car. The dealer has checked it over and told him that his car has a leak in the Eolys fluid tank and the DPF is having to regenerate too often. They have quoted £358 to repair it plus a further £1400 if they find that the DPF has been ruined.

There is a possibility that I will be replacing my car in a few months’ time – with the 2012 i30 or perhaps an i40. But the thought of high maintenance costs with a diesel car fitted with a DPF is of concern. The grunt and economy compared with a petrol car is nice to have – but being retired I can ill afford such high repair bills and have a sneaky feeling that a petrol car might be more suitable for my situation.
I

[Asterix]

Well, I don't allways know when the DPF regenerate on my car. Sometimes, when it does, and I stop at a light or so, it smells like a dead cat  Than I know it works.  I have tried a few times when i reset the L/100km counter the fuel consumption suddenly was very high for a few km's and then was normal again. I guess that's when it regenerates also. It would be nice if there was an indicator to show when it was regenerating.

If you have many short trips and the DPF isn't done regenerating, it will start again on the next trip. I have noticed in my car that a few longer trips at around 90 km/h do a lot good for the consumption. I drive 2x25 km a day with 4 persons in the car, and that normally gives me 5.6 L/100 but if i have some longer trips now and then, it will be a lot better, right now actually 5,2 L/100.

I don't know how old your car is, but if you only drive around 10.000 miles a year, and have many short trips, I would consider a petrol car next time.

I think the best my car have done so far, (2008 115 BHP 5 speed with 145000 on the clock) was 4,9 L/100 on a 200 km trip at main roads (90 km/h) and that is not ok for me when it is sold as 4,7 L/100 average.

[eye30]

Well, I don't allways know when the DPF regenerate on my car. Sometimes, when it does, and I stop at a light or so, it smells like a dead cat  Than I know it works.  I have tried a few times when i reset the L/100km counter the fuel consumption suddenly was very high for a few km's and then was normal again. I guess that's when it regenerates also. It would be nice if there was an indicator to show when it was regenerating.

Is there a sound from the unit when it is doing it?

[Asterix]

Well, I don't allways know when the DPF regenerate on my car. Sometimes, when it does, and I stop at a light or so, it smells like a dead cat  Than I know it works.  I have tried a few times when i reset the L/100km counter the fuel consumption suddenly was very high for a few km's and then was normal again. I guess that's when it regenerates also. It would be nice if there was an indicator to show when it was regenerating.

Is there a sound from the unit when it is doing it?

No I don't hear or feel anything when it regenerate. (...and I'm not an old bloke yet, so that's not the reason) 

[AlanHo]

OK - this might be a dumb question - but how do you know that the DPF is regenerating.?  I have no idea what to look for.  I can find no mention in the user manual and I cannot find any info on this forum - is this because DPF equipped cars are perhaps not sold in Australia (YET)

The KIA Ceed with the same engine seems to have an indicator in the instruments - according to things I have read on the KIA form - where it also mentions that it takes about 15 minutes to regenerate and the fuel consumption is very high for that period.

My car is Sept 2010 by the way.

[Asterix]

- where it also mentions that it takes about 15 minutes to regenerate and the fuel consumption is very high for that period.

My car is Sept 2010 by the way.

That's also my observation. But I only find out if it comes shortly after I have reset the consumption indicator.

If you have had the car for 15 month, and only done 11.000 miles, I would take the petrol...

[AlanHo]

Asterix

You mentioned that your car is a 2008 model. I had read that Hyundai did not introduce the Euro5 engine which had a DPF until early 2010. I wonder why your car has a DPF?

[Asterix]

As far as I know, all 115 BHP models in DK have DPF, the 90 BHP does not, or at least did not for the first few years. I actually don't know if the new 90 BHP have it today.

[Asterix]

...and it is not EURO 5, only Euro 4   

[asathorny]

Well, for the past two years I was thinking I went down the wrong path buying a petrol car...   I feel a bit better bout things now in that, I am not a high mileage guy and diesels getting quite pricey again and now Alan has caused me to do some google research and it seems that the DPF is a common and expensive problem for more than just a few...

 

[Asterix]

I hope I will not experience problems with the DPF. This is my first diesel car, but I have driven diesels before as part of my earlier job.

It is a nice car and it is much better to tow our caravan than our previous petrol car. 

[2i30s]

OK - this might be a dumb question - but how do you know that the DPF is regenerating.?  I have no idea what to look for.  I can find no mention in the user manual and I cannot find any info on this forum - is this because DPF equipped cars are perhaps not sold in Australia (YET)

The KIA Ceed with the same engine seems to have an indicator in the instruments - according to things I have read on the KIA form - where it also mentions that it takes about 15 minutes to regenerate and the fuel consumption is very high for that period.

My car is Sept 2010 by the way.

at the end of 2011 the i30 crdi in Australia still wasn't fitted with a dpf,I'm not sure if the 2012 models will be fitted with a dpf.  :confused:there are other Hyundai crdi variants fitted with a dpf in Australia though. 

[AlanHo]

I still don't know how to detrmine if and when the DPF on my car regenerates. I have never had any unaccountable drops in fuel consumption and the car has always driven normally. No sudden loss of performance, or change in egine noise, or smoke, or smell, or indications on the instruments. Totally nowt.

So how am I to know whether the DPF ever regenerates and whether it effects fuel consumption.

[Alasama]

What I learned is, DPF works generally around 700-800KM, but depends on actual condition of each car, and determined by ECU. DPF could need 15 mins to work. However, it could work when you were on high way and you never noticed it.
Did you ever feel the unusual massive vibration for seconds when the car is stopped ? We have many diesel owners with that experience. Everybody's sweating when it happens for the 1st time. People said that's due to DPF activated. I'm still wondering.
Indeed I have the experience for many times, the timing is when I stopped at a red light and there's a time I was in the parking lot (engine still on). My crdi has done 30000km so far.

[diablo]

Well, for the past two years I was thinking I went down the wrong path buying a petrol car...   I feel a bit better bout things now in that, I am not a high mileage guy and diesels getting quite pricey again and now Alan has caused me to do some google research and it seems that the DPF is a common and expensive problem for more than just a few...

 

I wondered about getting a diesel due to the huge fan base for them, but I had my doubts for my usage - which is mainly two mile trips with the odd 30 mile trip occasionally.

I didn't know about the particulate filter thing but thought that the high mpg of the diesel would only happen after it had warmed up after a few miles.

My 1.4 is more than enough for my town driving and motorway work and I very rarely need to overtake anything other than tractors on country roads, so I think I made the right choice.

[neoto]

@diablo: For a few mile trips, definately diesel is not a good choice. Mainly it needs more time to warm up (really high fuel consumption during this warm-up period). In the end, you pay more for it and get really insignificantly lower average fuel consumption than petrol...

I have been 'ranting' over DPF a lot on this forum (search), so I won't be long - as it was mentioned a few times already, most Australian diesel i30 don't have DPF fitted. There is a sticker somewhere in the motor compartment that says whether DPF is fitted or not.

Regarding your consumption, Alan - I have an average fuel consumption of 5.4 l/100km over last 34.000 km. I'm doing mostly highway driving at speeds 100-130 km/h. If I limit my speed to about 110 km/h, I get the fuel consumption of 4.5 l/100km.