[AlanHo]

Over the last couple of thousand miles I have been keeping an eye open for when the DPF regenerates and making a note of the corresponding odometer readings  .

So how do I know when it is regenerating?................ when there is no indication of it in the instrument display   
The answer is that I use one or both of two indicators.

•   I always have the trip display showing average fuel economy. If I notice a sudden increase in fuel consumption for no obvious reason I assume that this is due to the DPF being regenerated. I believe that this is effected by extra fuel being injected at the end of the power stroke in each cylinder, which burns in the exhaust, and raises the DPF temperature above 600 °C to burn off the carbon particles in the filter.

•   The second indicator is when I stop the car in traffic and the engine does not auto stop with a message “Auto Stop Deactivated” in the display. There is nothing in the manual to back up my assumption, but it is always accompanied by a sudden increase in fuel consumption.

It is not easy to spot when the fuel consumption suddenly increases so my odometer readings stating when regen started will not be dead accurate. However – the DPF regeneration seems to take about 20 minutes or 20 to 25 miles dependent on whether you are in town or motorway conditions at the time - so the figures cannot be a lot out.

Here are my results so far :-

Odometer           Increment
4798  miles                   
5062                       264
5580                       518* I possibly missed a regeneration
5853                       273
6101                       248
6624                       523* I possibly missed a regeneration
6885                       261
7140                       255

I’m not sure what conclusions you can draw from this – other than the DPF on my car appears to regenerate at approx. 260 mile or 420 km intervals irrespective of the sort of journeys being made.

What I do know is that the DPF is regenerating at least twice during every tank full of fuel – which means a total of 40 to 50 miles being driven at between around 30 to 40 mpg depending on the speed of the car at the time it occurs.

Without boring you with the maths – if my car can cruise for 240 miles at 60 mpg – it will then do the next 20 miles at 30 to 40 mpg. This drags the average down by 10% from 60 mpg to 56 mpg – a significant difference.

Hence there is no chance that us guys in Europe will be able to match the economy figures you Aussies can achieve.  However, the difference is not quite enough to cause me to want to emigrate.

[Doggie 1]

Hence there is no chance that us guys in Europe will be able to match the economy figures you Aussies can achieve.  However, the difference is not quite enough to cause me to want to emigrate.

But what about our weather....? 

[neoto]

 

This is much worse than the 2011 i30 I have... In my case, the regeneration is fixed to 700 km (435 miles) and it does 1-2 regenerations per tank.
How much does the MPG change in your case, Alan? My trip computer usually goes from 5 l/100 km (47 MPG) to 7 l/100 km (31 MPG), which results in ~2% increase in total economy figures (0,1 l/100km). It is not much but is definitely a joy-breaker  This equates to 25 kilometers less per tank...

[AlanHo]

This is much worse than the 2011 i30 I have... In my case, the regeneration is fixed to 700 km (435 miles) and it does 1-2 regenerations per tank.
How much does the MPG change in your case, Alan? My trip computer usually goes from 5 l/100 km (47 MPG) to 7 l/100 km (31 MPG), which results in ~2% increase in total economy figures (0,1 l/100km). It is not much but is definitely a joy-breaker  This equates to 25 kilometers less per tank...

See my previous post on the topic

https://www.i30ownersclub.com/forum/index.php?topic=16724.msg182314#msg182314

[i30niko]

Thank god we do not have those DPFs here in Australia.

THey seem to cause more problems than they solve.

{Apologies for not being of any help I just had to get that out of my system}

[jcd]

Thank god we do not have those DPFs here in Australia.

I'm glad to know that my i30 doesn't have a DPF. I have a DPF on my NS Diesel Pajero and although it never caused me any problems, I know a few people with similar cars that were forever having problems and it took a couple of years of ECU upgrades before Mitsubishi got the problem largely under control.

Bye Jeff.

[AlanHo]

Here is an update to my original post with two more regenerations

Odometer           Increment
4798  miles                   
5062                       264
5580                       518
5853                       273
6101                       248
6624                       523
6885                       261
7140                       255
7314                       174...Mainly town driving
7680                       366...Includes 280 mile motorway trip
8014                       334...60% motorway driving

[peon2t]

My new i30 has now 600 km on the clock and yesterday I noticed this "Auto Stop Deactivated" in the display and more important it smelled a bit unusual after I have parked the car. (And this unusual smell seems in fact to be not so unusual for cars which were just regenerating their DPF)

But I was a bit surprised to have a regeneration at 600 km. According to AlanHo's investigations this would be too late for the first but too early for the second. But maybe it's a bit different when the car is all new or there are other factors. (For example it could be possible that I missed and interrupted an earlier regeneration so that it decided to start again now.)

[Asterix]

There's a pressure sensor before and after the DPF. They compare readings in pressure and are used to define when to regenerate. I don't think it's fixed intervals. As your car is still very new, there's probably not very much soot in the DPF and thus there will be longer between the regenerations in the start.

[neoto]

There's a pressure sensor before and after the DPF. They compare readings in pressure and are used to define when to regenerate. I don't think it's fixed intervals. As your car is still very new, there's probably not very much soot in the DPF and thus there will be longer between the regenerations in the start.

Based on the regularity of the intervals on both the 2011 CRDi and newer, I seriously doubt that the regeneration is triggered by the pressure difference... Look at my posts to this topic - driving style, weather, fuel... nothing effects the regeneration interval.

[AlanHo]

I should point out that I record the odometer reading as soon as I notice any sign that the DPF is regenerating - such as a sudden and steady increase in the average fuel consumption or the Auto Stop being deactivated. I don't necessarily catch when the regen actually starts - hence my odo figures can be at any point in the regen activity (which seems to last for 15 to 20 miles).

Hence the intervals I have shown could be innacurate by plus and minus 20 miles.

As time goes by I am becoming more convinced that the regeneration is sponsored by either a pressure differential across the DPF or a maximum back pressure reading and not a set mileage interval. I have interrogated the service people at my dealership and they are not able to answer the question to my satisfaction - only that it is triggered by the engine "computer". It would be interesting to hear what other dealerships have to say on the subject - do we have any volunteers from Europe members to follow this up?

[Phil №❶]

I'd ask my dealer, but we don't have DPF here 

[neoto]

I faced the dealer with the data I recorded and they did not have any good explanation.
I can export the log of regenerations for the whole 61k kilometers, but on general it appears that the interval is fixed to ~700 km (the log is here: http://www.poraba.com/usage_other_view.php?type=25888&carid=11497)

[AlanHo]

I faced the dealer with the data I recorded and they did not have any good explanation.
I can export the log of regenerations for the whole 61k kilometers, but on general it appears that the interval is fixed to ~700 km (the log is here: http://www.poraba.com/usage_other_view.php?type=25888&carid=11497)

Where does the log information come from?  I would be interested to get the same info off my car - if only I knew how.

[neoto]

I faced the dealer with the data I recorded and they did not have any good explanation.
I can export the log of regenerations for the whole 61k kilometers, but on general it appears that the interval is fixed to ~700 km (the log is here: http://www.poraba.com/usage_other_view.php?type=25888&carid=11497)

Where does the log information come from?  I would be interested to get the same info off my car - if only I knew how.

At the moment, I am the logging interface...

However, it would not be hard to read the exhaust gas temperature and wait for the temperature to raise above 600 °C. I had a plan to do something like that but had not had time yet.

[AlanHo]

I faced the dealer with the data I recorded and they did not have any good explanation.
I can export the log of regenerations for the whole 61k kilometers, but on general it appears that the interval is fixed to ~700 km (the log is here: http://www.poraba.com/usage_other_view.php?type=25888&carid=11497)

Where does the log information come from?  I would be interested to get the same info off my car - if only I knew how.

At the moment, I am the logging interface...

However, it would not be hard to read the exhaust gas temperature and wait for the temperature to raise above 600 °C. I had a plan to do something like that but had not had time yet.

OK - but how do you recognise that the regeneration has started with such precision.

There is no indication in the instruments and it is not always easy to spot that the fuel consumption has increased.

[AlanHo]

I am sitting in a hotel in Cumbria typing this after a 176 mile cruise up the motorway from home. I was shocked to find that the DPF regenerated after only 157 miles from the previous regeneration.

When I started the trip the car had already done 74 miles - mainly in-town driving - since the previous regeneration. Then 83 miles into my trip (of which 85 miles were on the motorways at a steady speed on the cruise of 65mph) the DPF started to regenerate again which lasted for 24 miles.

I will not bore you with the maths but I made a note of the trip average economy at each point with the following result :-

First 83 miles - 3 on main roads and 80 on the M42 and M6 - average economy was 63.60 mpg (4.44 l/100)
Next 24 miles on the motorway whilst the DPF regenerated  - average economy was 47.33 mpg (5.97l/100)
Final 69 miles - 43 on motorway 26 on good main roads      - average economy was 62.15 mpg (4.55 l/100)

The updated table of regens now looks like this

Odometer           Increment
4798  miles                   
5062                       264
5580                       518
5853                       273
6101                       248
6624                       523
6885                       261
7140                       255
7314                       174...Mainly town driving
7680                       366...Includes 280 mile motorway trip
8014                       334...60% motorway driving
8171                       157...77 miles urban - remainder motorway

[Asterix]

Regeneration over 24 miles..

When cruising at 65 miles you're are doing 1900 - 2000 revs..

Would it make the regeneration faster if you changed to 5. gear at higher revs...

[AlanHo]

it so happens for the past month or two I have been keeping the engine revs at 2000 or above on the cruise.

The display tells me to change up from 4th to 5th and 5th to 6th at about 1750 rpm - but this drops the engine revs to less than 1500 rpm after you change gear. I have therefore delayed changing up so that the engine is doing around 2000 rpm in the next gear.

Why did I do this? I hear you ask. The answer is because the manual says that if the engine warning light comes on to indicate a forced regen is required - run the car at 2000 rpm for about 20 minutes. So I thought that if I kept the revs above 2000 rpm the soot would not build up in the DPF so quickly and the regen. intevals would be much longer.

How wrong can you be?..............

[Asterix]

Hmm, I would thought just like you....

Have this new gearchange point worsened your economy then...

[eye30]

Why did I do this? I hear you ask. The answer is because the manual says that if the engine warning light comes on to indicate a forced regen is required - run the car at 2000 rpm for about 20 minutes. So I thought that if I kept the revs above 2000 rpm the soot would not build up in the DPF so quickly and the regen. intevals would be much longer.

Why not drive "normally" and see what effect this has on the regen interval and time..

[AlanHo]

Why did I do this? I hear you ask. The answer is because the manual says that if the engine warning light comes on to indicate a forced regen is required - run the car at 2000 rpm for about 20 minutes. So I thought that if I kept the revs above 2000 rpm the soot would not build up in the DPF so quickly and the regen. intevals would be much longer.

Why not drive "normally" and see what effect this has on the regen interval and time..

That is the point - up  until recently I have been driving "normally".  By that I mean changing up when the car computer tellls me to. I have now established that keeping at 2000 rpm has not noticeably affected the car's economy and it has not helped extend the DPF regen intervals. What it does do is make the car far more lively and responsive.

[Phil №❶]

it so happens for the past month or two I have been keeping the engine revs at 2000 or above on the cruise.

The display tells me to change up from 4th to 5th and 5th to 6th at about 1750 rpm - but this drops the engine revs to less than 1500 rpm after you change gear. I have therefore delayed changing up so that the engine is doing around 2000 rpm in the next gear.

Why did I do this? I hear you ask. The answer is because the manual says that if the engine warning light comes on to indicate a forced regen is required - run the car at 2000 rpm for about 20 minutes. So I thought that if I kept the revs above 2000 rpm the soot would not build up in the DPF so quickly and the regen. intevals would be much longer.

How wrong can you be?..............

I suspect Alan that the instructions to run @ 2k allow enough excess fuel to be injected to burn off the soot, not to keep the DPF clean, so it's a matter of personal choice what revs you use in between. 

[neoto]

I faced the dealer with the data I recorded and they did not have any good explanation.
I can export the log of regenerations for the whole 61k kilometers, but on general it appears that the interval is fixed to ~700 km (the log is here: http://www.poraba.com/usage_other_view.php?type=25888&carid=11497)

Where does the log information come from?  I would be interested to get the same info off my car - if only I knew how.

At the moment, I am the logging interface...

However, it would not be hard to read the exhaust gas temperature and wait for the temperature to raise above 600 °C. I had a plan to do something like that but had not had time yet.

OK - but how do you recognise that the regeneration has started with such precision.

There is no indication in the instruments and it is not always easy to spot that the fuel consumption has increased.

Well, firstly, I usually keep an eye on the current fuel consumption, secondly, I can predict the next cycle to the 10-20 km. Then it is not hard to spot the 2-3 l/100km more and slightly different engine sound. And I have the feeling that it pulls much harder in lower rpm (I have 90 PS and any change is very obvious).

[AlanHo]

I am now back home from Cumbria via a diversion to Oldham where I had a noise insulation kit fitted by a specialist company called Noise Killers. See separate thread (when I post it later after I give the car a run on the same roads I used before, to take comparative decibel meter readings.)

The DPF regenerated again on the way home on the motorway. It lasted about 14 miles and economy during regeneration was 46.05 mpg. The average for the whole 411 mile trip was 60.1 mpg. As before I cruised the motorways at around 65 mph and generally kept to the speed limits on urban roads. The trip included driving over the Kirkstone Pass in the Lake District - a very steep and winding alpine type road which climbs from a low of 174 feet to a high of 1505 feet (according to the sat-nav) which was very icy and had a snow covering in parts. This would have knocked econonomy back a touch.


Odometer           Increment
4798  miles                   
5062                       264
5580                       518
5853                       273
6101                       248
6624                       523
6885                       261
7140                       255
7314                       174...Mainly town driving
7680                       366...Includes 280 mile motorway trip
8014                       334...60% motorway driving
8171                       157...77 miles urban - 80 miles on a motorway
8480                       309...83 miles urban - 226 on motorways

[eye30]

After reading about the DPF regen I'm glad I've a petrol.

Although I had a diesel previously it didn't regen.

[neoto]

After reading about the DPF regen I'm glad I've a petrol.

Although I had a diesel previously it didn't regen.

Well, I drove the new i30 with 1.6 GDI (135 BHP) last week and I was kind of disappointed. Usually, I do around 80-90% of driving on motorways and my 90 BHP 1.6 diesel feels way more responsive in higher gears at speeds of 100-130 km/h. This together with the lower fuel consumption makes the diesel a simple choice to make. DPF regens are pain in the ass mostly due to 'unpredictable' behaviour and lack of proper explanation by the dealers.

[AlanHo]

Latest update after a long trip to Cumbria. Last entry of 391 miles comprises :-
First day
Two cold starts. 205 miles on motorway, 24 miles in 1st and 2nd gears crossing mountain passes. 50 miles on fast A roads. 8 miles urban.
Second day
One cold start. 1 mile on B road. 88 miles on motorway.

During the trip the overall average according to the trip recorder was 56.29 mpg - but during 22 miles of DPF regen the car averaged 34.6  mpg. Excluding regen the average would have been 58.4 mpg

I am satisfied that this trip has fully confirmed that my car does not regenerate at a set mileage - but when the DPF calls for the requirement which I presume is based upon pressure drop across the DPF itself. 


Odometer           Increment
4798  miles                   
5062                       264
5580                       518
5853                       273
6101                       248
6624                       523
6885                       261
7140                       255
7314                       174...Mainly town driving
7680                       366...Includes 280 mile motorway trip
8014                       334...60% motorway driving
8171                       157...77 miles urban - 80 miles on a motorway
8480                       309...83 miles urban - 226 on motorways
8635                       155...Mainly urban journeys
9026                       391...During a 408 mile round trip on motorways to Cumbria

[Keith]

I'm with eye30, Post#25.... diesels have become too finicky in order to stay within pollution regulations,... in my opinion. 

[Doggie 1]

Not in Oz.