DPF / Short journeys debate

jpaul said:
The wear&tear, as said, maybe a strong reason to avoid 30s journeys.

Castrol used to advertise 75% of engine wear during warm up, so - what does that translate into ?
if you have two cars both with 50k miles but one has 1/2 as many cold starts, that one will have 1/2 the wear (or so ?, anyone good at man maths);
so even if the emissions are in check, mpg might be going south and reliability, for the next (post pcp) owner;
(the diesels going to be taking longer to warm up too, so more wear, and the dpf has a limited number of life cycles)

seems a pity as a buyer you cannot demand to hook up on the OBD interface and get that data plus the number of regens.
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The issue is the manufactures are aware of the inconvenience of driving a modern diesel, due to their complex system fitted to meet emissions targets. They won't even fit a light or allow a warning to easily identify when a regeneration is happening. F I'm their point of view, and I partially agree with them, any sign of warning would cause panic and people pesting the dealer for info, without checking the manual first.
Most of the people assume car as just a way to connect a to b, but their complexity makes that a dangerous assumption. And penny pinching most of the time will backfire. Clearly we can't have it all.
I love the 60mpg+ of a 2.0 diesel, but I'm aware of the inconveniences and possible costs in the long run. But someone doing, let's say 5k miles, mpg should be the last thing to worry about, as I don't believe that person will be driving a V8.
In the other hand, the popularity of SUVs, which are aerodynamically poor and heavy, are the perfect scenario for a diesel engine, where the mpg would be acceptable, but as most are just a replacement for a city car, the sensible option would be a good petrol engine, not the anemic small strained engines, but who's willing to see mid or low 20s mpg?
The idea of be able to check the DPF ia fantastic, but only for the actual owner or a potential buyer, never for the manufacturer or the seller.
 
Thankfully not had any problems with my 2013 Octavia. Sometimes even after a shirt drive you gear the DPF come on and stop on even after you turn the engine off. So I think some cars have got around the DPF regen interrupt that way.

My other half has an i30 that she very rarely took on long drives, for about 5 years, and it never gave her a problem. Seems manufacturer specific to me.
 
kissenger said:
Thankfully not had any problems with my 2013 Octavia. Sometimes even after a shirt drive you gear the DPF come on and stop on even after you turn the engine off. So I think some cars have got around the DPF regen interrupt that way.

My other half has an i30 that she very rarely took on long drives, for about 5 years, and it never gave her a problem. Seems manufacturer specific to me.
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Mine will happily regen sat at the traffic lights as long as the car is up to temperature. Doesn't use adblue either. Easy to spot when it's doing it as well, will go from 0.1gph to 0.2 when idling.
Barely ever does a regen though maybe one a year that I notice.
 
is miles a car has travelled a very blunt tool to establish wear/useable life left in a diesel engine/dpf system , had just read below estate thread post.

and, if anything, you know the cars with the higher mileage have probably done longer trips, (could have been a cab I suppose), where the smaller mileages, could be less frequent long journeys, short journeys, or clocking ... and no means to determine which

L&K spec, there's much less about and unless you're happy with very high miles, you won't get one for £12k. £14-15k minimum. There's an L&K TDi DSG estate on ebay at the moment, 1 ownwer and £12,800, 2018, but it's done 78k.

I'm waiting to pounce on a DSG TDI L&K estate with under 50k miles, with factory towbar and panoramic roof, when one comes up for sale. I'm expecting to have to pay £17-18k, the cash is literally burning a hole in my bank :p:D
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jpaul said:
is miles a car has travelled a very blunt tool to establish wear/useable life left in a diesel engine/dpf system , had just read below estate thread post.

and, if anything, you know the cars with the higher mileage have probably done longer trips, (could have been a cab I suppose), where the smaller mileages, could be less frequent long journeys, short journeys, or clocking ... and no means to determine which
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Yes.
Problem is what else can you use.

When I got my second car my old man was running a fleet and asked the garage owner who the cars went through his advice for a youngster moving on from his first trash car if an older 30k miler or a younger 60k was. The guy said definately the younger, older cars with low mileage tend to have done far more short journeys than younger with high mileage. But its still a gamble, you may end up with a young one thats done many miles over a short period because the guy running it was something like a delivery guy as their job.

All you can say really is that some things tend to fail more based on age as opposed to mileage, generally electrics, things like sunroof seals just decay over time.
 
Maybe a solution, if manufacturers, or individuals can get the usage infromaation, they could get a premium for their car
..... you would pay extra for that information on the car history, versus those cars that did not disclose it. ... carrots
 
jpaul said:
Maybe a solution, if manufacturers, or individuals can get the usage infromaation, they could get a premium for their car
..... you would pay extra for that information on the car history, versus those cars that did not disclose it. ... carrots
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But you would be reliant on manufacturers to implement it and to them the concerns of older cars etc helps them sell new ones to those that can afford it.
They would appear to be little/no benefit for them of detailed tracking stats of a car.
 
Mine actually did a regen yesterday, noticed a slight judder at idle switched to instant fuel consumption and sure enough it was. Took about 20 minutes until it was happy.
 
I am not sure how people notice their cars "doing a regen". I have driven my E350 (first car i have owned with a DPF) up to 141k miles now, and i am yet to notice it doing anything whatsoever :p
 
Jez said:
I am not sure how people notice their cars "doing a regen". I have driven my E350 (first car i have owned with a DPF) up to 141k miles now, and i am yet to notice it doing anything whatsoever :p
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Like I've said before it will go from 0.1gph to 0.2gph at idle and the car shudders, very slight though only the driver noticed it kind of thing.
 
Mercedes dont have an idle consumption readout, so i guess that is one less clue :) Perhaps they ironed out any additional shaking, the Merc V6 diesel engine is very smooth for what it is, you dont feel it running really.
 
I got Proof that short trips KILLS dpf.... In my work Transit DPF DIED last week 3000 miles from dealer. I had to clean it every 280-300 miles with 20 miles blast to M1 and back. After Doing it aroudn 12 times ITS GONE. Cant get cleaned anymore needs replacing now...
3000 MILES !!!! Brand new 2.0 Ford Transit Custom.
 
Zeed said:
I got Proof that short trips KILLS dpf.... In my work Transit DPF DIED last week 3000 miles from dealer. I had to clean it every 280-300 miles with 20 miles blast to M1 and back. After Doing it aroudn 12 times ITS GONE. Cant get cleaned anymore needs replacing now...
3000 MILES !!!! Brand new 2.0 Ford Transit Custom.
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Sounds like something wrong with that van - we run a variety of diesel vans at work under different scenarios including some that only do short trips both frequently and infrequently while others will be driven all around the country and DPF issues are pretty rare.

EDIT: Infact similar to my personal experience EGR related complications seem more common at work than DPF. They had one off for work couple of days back due to EML coming on with an indicated EGR fault.
 
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Rroff said:
Sounds like something wrong with that van - we run a variety of diesel vans at work under different scenarios including some that only do short trips both frequently and infrequently while others will be driven all around the country and DPF issues are pretty rare.

EDIT: Infact similar to my personal experience EGR related complications seem more common at work than DPF. They had one off for work couple of days back due to EML coming on with an indicated EGR fault.
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It's going in to dealer soon Ill update outcome.. Atm it says No engine start in 350 miles..... Driving conditions.... Running constantly on unheated engine with 300 yards stop start building to building around campus.... Quite possibly worst driving conditions average is 20mpg :D

So far It's been back to dealer with Faulty up hill brake assist that used to lock brakes WHILE DRIVING at random. Image doing 30 and brakes randomly lock up on straight almost crashed the ****** 2 times cause of it !!!
 
3008SUV 2017 10k Miles diesel.

According to the manual, the car will complain if it really needs a regen but I have never seen it. It gets used for longer journeys which normally are over 40mph and not for the daily 8 minute work trip.

There’s no cockpit display to say the car is performing a regen. I wish it would so if it’s started I would just keep driving until it’s complete.
 
Our Amarok used to occasionally display a light on the dash and upon checking the manual, would suggest we drive at a high speed in a low gear for at least 15 mins! We would and it would be happy.

Our Kia, touch wood has never indicated any issues but it does get a blast regularly.
 
A slight bump as I've noticed my 2.2d Mazda 6 seems to regen more often than I think it should and it takes longer than I think it should. It's done 73k miles and although I'm not getting any dpf warnings, I'm going to get the dpf washed. It'll be interesting to see if I notice an difference in regen frequency, power and mpg afterwards.
 
Feek said:
A slight bump as I've noticed my 2.2d Mazda 6 seems to regen more often than I think it should and it takes longer than I think it should. It's done 73k miles and although I'm not getting any dpf warnings, I'm going to get the dpf washed. It'll be interesting to see if I notice an difference in regen frequency, power and mpg afterwards.
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For what it's worth my 6 does a regen every 150 to 200 miles depending on what kind of driving I've been doing. Other 6 owners Ive spoken to report similar. mpg usually drops by about 25% and the regen takes 15 to 20 minutes. Be careful when interrupting a regen on the Skyactive diesels as unburnt diesel in your filter drains into your sump and dilutes your oil.
 
rpmmatt said:
For what it's worth my 6 does a regen every 150 to 200 miles depending on what kind of driving I've been doing. Other 6 owners Ive spoken to report similar. mpg usually drops by about 25% and the regen takes 15 to 20 minutes. Be careful when interrupting a regen on the Skyactive diesels as unburnt diesel in your filter drains into your sump and dilutes your oil.
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Mine is doing it more frequently than that, I've known it to happen twice on my trip into the office which is only 120 miles and yes, I know about what happens when a regen is interrupted - I check the oil regularly and if the level starts to go up on the dipstick then it's time for a mid-service oil change.
 
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