Diesel and DPF - Dingle232

When I bought my car last year (TDi) I was doing regular 60 mile motorway trips 2 or 3 times a week. Since then my circumstances have changed dramatically and I am now finding myself doing mainly town driving for short distances and I suspected that this may become an issue in time.

I am finding that the car is performing regens more and more often but have been caught out by quite a few of them (not realising - quite why clever manufacturers can't 'invent' a dashboard notification is beyond me) where I have killed the engine before it's been fully completed. Each time i have made sure the car's next run is a lengthy one at higher speeds and have noticed no repetition....until the next time when I have reverted to town driving once more. The need for me to have to take the car on a run purely to negate this is becoming irritating.

I am at a point where I realise I probably need a petrol/hybrid engined powered car and am starting to think about that. My question is if the incomplete regens are actually damaging the car I have at the moment if I continue to stop driving before the cycle is completed?

If not then I'll persevere for a while before looking to change, but if it's detrimental then I can speed that process up.

Diesel and DPF - gordonbennet

The failed regens won't be helping the DPF, but if the runs you give it are allowing them to complete then you could probably go on like this for some time, maybe try and be more sensitive to when a regen has started..

Quite why car makers seemingly assume their customers are all as thick as two planks and all incapable of taking notice (and action) if a 'regen in progress' light was on the dash is a question only they can answer...in almost all trucks you will find not only a warning light or message of regen in progress, but one button to cancel an automatic regen if it can't complete and another button to trigger a static regen if the on board menu informs DPF levels are too high...it can be done, Toyota did this with some of their large 4x4's too.

In your case Dingle i would be keeping an eye on engine oil levels, failed regens could be allowing fuel to be finding its way into the sump, any sign of increasing engine oil level i would change the oil sharpish, even if its not increasing i'd bring forward your engine oil change intervals to maybe twice a year, starting today...cheap peace of mind if you buy oil (anything basically of the right spec) in 20 litre packs and grab half a dozen oil filters when they're on less than half price offer.

The other issue is the EGR is probably working overtime, that might need cleaning out (filthy job, sometimes the inlet manifold needs cleaning out too) at some point, and whilst on northsouth layouts access isn't usually too bad on transverse engines access can be a nightmare making EGR replacement (dealers likely to fit new only) an expensive job involving many hours of work.

Edited by gordonbennet on 28/02/2024 at 04:42

Diesel and DPF - Dingle232

Thanks gb, as always, a well-reasoned and informative response which I appreciate.

In summary I share your view that it's somewhat of an issue. I think the main bug bear for me is going to be the fact that I seem to keep missing the regens and that's something that's likely to continue happening. Not deliberately but there's clearly a reason it's happening and that's probably me :-).

Whilst the other interventions around regular runs and oil changes are eminently sensible it feels to me like I am having to work harder for the car than it is for me. My driving now just doesn't lend itself to regular runs, so I am finding it irritating to have to take it for the sake of it. Similarly, I understand your point re oil changes and whilst I'd completely accept it's not a massive job it's just one I don't want to have to do with that amount of regularity. Or at all if honest. But I think you are right in that it may be an issue with the problem I am having.

Talking to the Mrs. last night (as I do sometimes) I think we have both concluded that this is just an unfortunate consequence of the change in circumstances and that the diesel is probably the wrong car for us. We couldn't possibly have known so we're not beating ourselves up about it, and we just need to move on and look at changing to a petrol or hybrid and commit to its long-term use. We are going to consider that.

Which brings me to the inevitable question of which one. I must admit I never thought I was an Audi man before now as, with the exception of the odd BMW most of my cars have been Toyotas or Hondas as reliability has been a proven factor. I am tempted to swap the Q5 for another one in TFSi-e guise (PHEV) but am very nervous about an Audi long term, especially the DSG gearbox element of it. I am planning to retire in the next couple of years so my ability to pay for any expensive repairs, should they happen, will be diminished. It's a real shame because unless I can convince myself/us that a different Q5 will not be a future money pit then my hesitation will remain. The Q5 is brilliant, and I have thoroughly enjoyed owning it probably more than any other car I have had.

Perhaps SLO76 may have some insight into this in terms of the long term reliability?

My inclination would be to look at a RAV4 or if I can afford it as new a Lexus NX as I can afford. Neither excite me particularly but I trust the brands and know I am extremely unlikely to have an issue with their 10-year warranty option.

Got some thinking to do.

Edited by Dingle232 on 28/02/2024 at 08:37

Diesel and DPF - gordonbennet

I agree that Hybrid is probably the way to go, and (i'm being honest here not just because i like Toyotas) Toyota have hybrid down to a T, every taxi driver can't be wrong and there's no denying they have the best rep when it comes to standing by their product should something go wrong.

We'd planned to swap the Forester for a Corolla hybrid estate ourselves this year however some proposed changes at work (i'm part of the negotiation) might well see me retiring or otherwise being got rid of later this year or early next year, in which case we'll probably go down to one car and just keep the old Landcruiser going, which still seems bombproof.

I get your point re having to work more for the car that it does for you, it would really annoy me having to drive nowhere to fulfil the needs of the blasted DPF, i've only had to do that twice in the last 6 years at work with DPF equipped trucks which decided to start regens before arrival back at base, thankfully trucks tell you whats happening otherwise i wouldn't have had a clue, both times 5 miles up the dual carriageway and back saw regens completed.

Whist i'm not a fan of oil extractors one woud make good sense in your case until you decide what to buy next, you could probably forgo the interim oil filter change (sods law says thats underneath and requires half an acre of plastic undershield removing for access) so just swap a sumpful of contaminated engine oil for fresh for mid term changes? no raising of car or crawling round in the dirt necessary.

Diesel and DPF - Andrew-T

I get your point re having to work more for the car that it does for you, it would really annoy me having to drive nowhere to fulfil the needs of the blasted DPF,

Whenever I hear these comments I am reminded of my 2008 (probably final) purchase from a franchised dealer, of the 207SW which is still outside the front door. It has the 1.6 diesel engine, which was available then in two versions - 90 and 110 - one with, the other without a DPF. I checked with the salesman, who confirmed that my car had no DPF (they came in soon afterwards) and said I was probably better off without one. So these tales always give me a wry smile. This 207 has probably been the most trouble-free car I have owned - part of the reason it is still here.

Diesel and DPF - corax

I agree that Hybrid is probably the way to go, and (i'm being honest here not just because i like Toyotas) Toyota have hybrid down to a T, every taxi driver can't be wrong and there's no denying they have the best rep when it comes to standing by their product should something go wrong.

We'd planned to swap the Forester for a Corolla hybrid estate ourselves this year

That is on my radar too, if prices go down a tad, but I have not sat in one. I'm hoping that they are more spacious than the Auris hybrid because I found the cabin and seats a bit small for me (5ft 11). Ride quailty in the Auris isn't especially good anyway.

Diesel and DPF - Heidfirst

That is on my radar too, if prices go down a tad, but I have not sat in one. I'm hoping that they are more spacious than the Auris hybrid because I found the cabin and seats a bit small for me (5ft 11). Ride quailty in the Auris isn't especially good anyway.

I don't think that the Corolla estate is massively bigger than the Auris althughg the seat design may have changed. However, I believe that the ride quality is much improved (subject to wheel/tyre fitted & trim e.g. I would not be buying a GR Sport myself or probably even an Excel).

With my own Avensis approaching 7 I too am now starting to gather info as I tend to buy cars ex-demo/1 year old etc. so e.g a 2024MY Corolla or RAV4 I would be looking at buying in 2025.

Diesel and DPF - gordonbennet
I believe that the ride quality is much improved (subject to wheel/tyre fitted & trim e.g. I would not be buying a GR Sport myself or probably even an Excel).

The sportier higher spec appear to be on 18" wheels, if we get one its going to be sat on 16", a read of the owners forums speaks of crashing ride quality on the larger wheels which any of us here would have guessed would be the case.

Diesel and DPF - Big John

We'd planned to swap the Forester for a Corolla hybrid estate ourselves this year

That is on my radar too, if prices go down a tad, but I have not sat in one. I'm hoping that they are more spacious than the Auris hybrid because I found the cabin and seats a bit small for me (5ft 11). Ride quailty in the Auris isn't especially good anyway.

Likewise I had the Corolla on my radar and the mechanically identical Suzuki Swace now ruled out for me re headroom and B pillar intrusion. I'm circa 6ft 4" .

Diesel and DPF - RT

I have a similar dilema - 8+ years ago I bought my supposedly final car, an over-indulgent VW Touareg with most of the options ticked - my usage pattern is a mixture of daily short trips, monthly long journeys and about 20 weeks a year touring with a caravan.

3 years ago I bought an elderly Citroen C1 to do the daily short trips and save the big diesel from clogging its DPF, but it's annual mileage was under 1,000 so sold it on as uneconomic.

I now just make a point of doing a long run at least once a month, going out for a jolly if one doesn't occur naturally - whilst I wouldn't now buy a big diesel if I was starting from scratch, the increased depreciation by changing now is far more than the cost of a pointless long run once/month.

Diesel and DPF - daveyjp

My last diesel was a 2008 model and my mileage changed from 20k a year to about 8k. The diesel hated it, regular regens and dilution meant oil changes every 5,000 miles. It also killed the EGR so I moved it on.

Diesel and DPF - Gibbo_Wirral

In the Peugeot community, the heated mirrors come on during a regen - so some owners put a little LED in the circuit to give a handy notification

Diesel and DPF - gordonbennet

In the Peugeot community, the heated mirrors come on during a regen - so some owners put a little LED in the circuit to give a handy notification

Brilliant, was that designed so PSA vans could have a maker fitted regen warning on the dash? would make sense though i'm not even sure if PSA or any other vans are so equipped.

Something similar should be possible for many different makes and models, if such a warning light were able to be fitted an Auris 1.4 Diesel (one of the best small Diesels around) estate could be a handy runaround and dog carrier option for us, food for thought there, thankyou.

Diesel and DPF - Dingle232

In the Peugeot community, the heated mirrors come on during a regen - so some owners put a little LED in the circuit to give a handy notification

If only Audi would do something so simple :-)

Diesel and DPF - Andrew-T

In the Peugeot community, the heated mirrors come on during a regen - so some owners put a little LED in the circuit to give a handy notification

Just wondering what the logical connection is between heated mirrors and a diesel regen ... ??

Diesel and DPF - Adampr

In the Peugeot community, the heated mirrors come on during a regen - so some owners put a little LED in the circuit to give a handy notification

Just wondering what the logical connection is between heated mirrors and a diesel regen ... ??

No-one said they were designed to switch on :)

Diesel and DPF - Dingle232

Done quite a bit of research since yesterday and whilst I am not ready to change just yet it looks like quite the conundrum if I move to a hybrid as there are lots of options on RAV 4's and Lexus NX's.

What are people's view on whether the Lexus is worth the premium over the RAV? Aesthetically I'd suggest it's the nicer looking car but there's a cost of around £6-10k over the RAV4.

Interesting dilemma to have.

Diesel and DPF - gordonbennet

Nice dilemma to be struggling with...can you spare £5 for a cup of tea guv? :-)

Maybe worth looking up typical menu servicing costs for the two vehicles if those are your shortlist, not just servicing look up what a typical full set of discs and pads all round would cost, convenience of the two dealerships...though you should only be visiting once a year and both are pleasant places to drink good coffee and munch decent biscuits in.

Insurance cost differences? Tyre costs?

I assume that Lexus warranty is same as Toyota so long as annual servicing is continued?

Diesel and DPF - Dingle232

For you gb - I can manage that. :-)

I did yesterday actually though I will revisit for costs of some of their consumables so that is a good shout, thank you. A big factor is that my nearest Toyota dealer is extremely good, from previous exeperience, and their costs were always reasonable along with exemplary service.

Lexus are definitely more expensive and whilst that isn't prohibitive, their dealer is some way away and I have no experience of them at all, though reviews are generally good.

We are in the camp of 'buy once buy well' so as it stands the RAV4 is the better value proposition despite not being as 'nice' a car to us. Between the ones we have identified there is around a £7k price difference that's hard to justify. Ouch.

Diesel and DPF - Heidfirst

We are in the camp of 'buy once buy well' so as it stands the RAV4 is the better value proposition despite not being as 'nice' a car to us. Between the ones we have identified there is around a £7k price difference that's hard to justify. Ouch.

if buying new there may also be the availability issue to consider - at one point Toyota UK stopped taking orders for the RAV4 because they had sold production so far forward, not sure what current lead time is.

Diesel and DPF - galileo

For you gb - I can manage that. :-)

I did yesterday actually though I will revisit for costs of some of their consumables so that is a good shout, thank you. A big factor is that my nearest Toyota dealer is extremely good, from previous exeperience, and their costs were always reasonable along with exemplary service.

Lexus are definitely more expensive and whilst that isn't prohibitive, their dealer is some way away and I have no experience of them at all, though reviews are generally good.

One of my more affluent mates has had more than on new Lexus. He lives a few miles South of Huddersfield and the Lexus dealer collected his car for servicing in Bradford and returned to his door.

Not sure if they still do that now, though.

Diesel and DPF - RT

I'd have thought the RAV4 was in between the Lexus NX and RX in terms of size, so not really comparing like-for-like

Diesel and DPF - Dingle232

If you look at the sizes on car size comparator, they are broadly similar, not a massive difference between them so I think it's a fair comparison to make. Anyhow, it's mor ethe hybrid element that's important to me and whichever one I choose there's little doubt they are the strongest contenders for being good hybrids.

Edited by Dingle232 on 29/02/2024 at 11:26

Diesel and DPF - focussed

In the Peugeot community, the heated mirrors come on during a regen - so some owners put a little LED in the circuit to give a handy notification

Just wondering what the logical connection is between heated mirrors and a diesel regen ... ??

Possibly to add some load to the engine via the alternator to help keep engine coolant temperature up.

Athough the power consuption of a couple of heated mirrors isn't going to be a lot of help, unless other electrical items are also switched on at the same time - maybe they are?

A combination of the heated mirrors + heated rear window + heated seats might make more difference.

Diesel and DPF - madf

I think a regen may work better or faster if the engine is under load.. switching on the heaters will mean the alternator will work to to meet the extra current drain.. thus meaning the engine will be doing more work.

Diesel and DPF - RichardW

Just wondering what the logical connection is between heated mirrors and a diesel regen ... ??

It turns on the HRW and mirrors to increase the load on the engine and help get the exhaust gas temp up.

Diesel and DPF - gordonbennet

In the Peugeot community, the heated mirrors come on during a regen - so some owners put a little LED in the circuit to give a handy notification

Not for the mirror heater itself but something else that needs to be working correctly, in the mirror housing in this case.

www.youtube.com/watch?v=9PL8P6AjSkM

I can relate to this, previous truck the outside temperature gauge started to read wrong, according to the dash it was probably reading 10/15' higher than the actual temp.

At the same time the vehicle, which used minimal adblue anyway being part EGR design started using less and less and eventually stopped using any at all when the temp started getting towards 40' on the gauge during warm weather, also the torque had dropped off a little.

Turns out that simple outside temp reading is far more important than one might think, replaced temp sensor and everything good again.

Purely out of interest a new truck exahust silencer/DPF can easily run into 5 figure sums, around year 4 the DPF itself started breaking up, the stainless silencer housing can be quite quickly dismantled and a new DPF cone was fitted and the thing that caused it, a failed adblue pump was also replaced, that would have been very expensivepump alone some £2000 but vehicle was under full R&M lease contract so all such repairs included.

The mobile chap in the link is worth watching.

Edited by gordonbennet on 02/03/2024 at 11:05

Diesel and DPF - madf

Any company putting a MAJOR IMPORTANT sensor on a wing mirror - notorious for being hit by passing traffic - employs half wits or cheapskates as design engineers.

Oh it's French - a Renault..

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