I have had some issues with my car with the dust particulate filter error coming up on the dashboard. I wasn't sure what fluid my car used, so I put in a bottle of Redex DPF cleaner with my tank of fuel. I did this about a month ago and since then I have had no issues - the car appeared to do a regeneration whilst I was driving it down the motorway and the error code disappeared (it hasn't appeared since).
However, tonight I've had my car towed to my garage as an engine fault error came up and it went into limp mode (18 mph along the motorway). The breakdown man said it was an error fault with injector number 1, however, that was only replaced 2 months ago (as the limp mode issue happened then), but when restarting the car, the breakdown man said that the injector error fault had disappeared.
I'm now wondering if the issue is with the Redex DPF cleaner that I have been using? I'm saying this, as I have just found some paperwork (from the previous owner) for the car, saying that in 2019, Pat Fluid Fuel Borne was added to the car - on looking that up, doesn't that mean that my car uses an Eolys system for regeneration? Also, I am wondering if the current engine warning issue is due to my adding the Redex DPF cleaner instead of what should have been Pat Fluid (I have had no error message coming up on the dashboard to say that the Eolys system needed topping up). I did not even know what a DPF was until about a month after I had bought the car, as my previous Citroen Xsarra Picasso diesel car did not have one. The garage will probably look at the car in the next day or so, but I'm wondering if I should ask them if the Redex DPF cleaner could have caused an engine issue? Any advice would be appreciated. Thank you.
However, tonight I've had my car towed to my garage as an engine fault error came up and it went into limp mode (18 mph along the motorway). The breakdown man said it was an error fault with injector number 1, however, that was only replaced 2 months ago (as the limp mode issue happened then), but when restarting the car, the breakdown man said that the injector error fault had disappeared.
I'm now wondering if the issue is with the Redex DPF cleaner that I have been using? I'm saying this, as I have just found some paperwork (from the previous owner) for the car, saying that in 2019, Pat Fluid Fuel Borne was added to the car - on looking that up, doesn't that mean that my car uses an Eolys system for regeneration? Also, I am wondering if the current engine warning issue is due to my adding the Redex DPF cleaner instead of what should have been Pat Fluid (I have had no error message coming up on the dashboard to say that the Eolys system needed topping up). I did not even know what a DPF was until about a month after I had bought the car, as my previous Citroen Xsarra Picasso diesel car did not have one. The garage will probably look at the car in the next day or so, but I'm wondering if I should ask them if the Redex DPF cleaner could have caused an engine issue? Any advice would be appreciated. Thank you.
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sorted byYes, the DPF filter has a finite life, usually around 170k. However that is dependant on your driving / engine etc. You can take one to 250k easily. The carbon is heated up to a temperature that it oxidises, and leaves the DPF as carbon dioxide gas... however bits like metal particles in engine oil etc can't be burnt off and forever remains. This is the "ash" which over time clogs up the DPF. Cleaning *can* work but in limited scenarios but generally replacement DPF's aren't too expensive and better to replace - most mech's dont want to do the cleaning because while it's being cleaned, your car is stuck on their ramps.. for a day or two.. or more, which takes up their money.
Siemens Injectors usually last around 200k, the Delphi / Bosch one's go for 250-300k before showing issues generally. If you start getting injector issues, it is vital you check the fuel filter, if there's glitter at the bottom, of the fuel pot, it means the fuel pump has been wearing away the hardened casing and has clogged the injectors - It is VITAL you NEVER run a diesel on empty. Fuel light comes on... yes you can drive for another 70 miles but you really do it at your peril. Aim to fuel up at an 1/8 of a tank.
Clogged DPF's do not affect the injectors. Even when the engine light comes on, there is enough flow - you would need serious engine running issues before you'd do damage to the injectors. Most likely you'd have turbo etc failure first, well before injector.
If you don't do a lot of miles, do NOT buy a diesel. It's seriously not worth it. You need to do atleast 15k before it makes sense over a petrol.
Going to the OP's problems - injector short to ground issues could easily be wiring - garage would need to check the resistance of the injector using a multimeter. That fault code doesn't necessarily mean the injector was faulty! How well do you know your garage? How well do you trust them? It could also be a transient fault... and a low battery voltage, like when the car has been stood for a year can cause all sorts of faults to appear. Or if the injector was left disconnected due to other work accidentally, it's why a decent diagnostics system (ideally Diagbox) would tell you WHEN the fault occured. If it was a long time ago, it's safe to assume it's a transient fault!!
Engine oil needs to be C2 rated, not C3!!
This is when going to a decent specialist who knows these engines and how to diagnose is vital.
It is only PSA engines (Peugeot / Citroen / DS) which use DPF fluid (Plus whoever uses PSA diesel engines, such as Ford). The other manufacturers use injection delay strategies etc. I prefer the PSA route - engine oil dilution is a VERY real problem with other cars, which means knackered engines at 150k if not caught.. plus the DPF fluid costs £120 incl labour for 100-150k miles of driving!
Newer PSA cars use DPF fluid along with Adblu. The two are not the same. Adblu is to reduce NOx emissions, DPF fluid lowers the temperature the soot combusts at.
The DPF fluid supplied by PSA is manufactured by Solvay (for 90%+ of cars). They retail their own brand, "Eolys" and rebranded by many other companies such as Bosal, Walker etc. It MUST be branded EOLYS to be the genuine stuff. PAT fluid is completely third party and would NOT use this for the reasons below:
There are 4 generations of EOLYS fluid and which one you use in your car is VERY important. You can't mix and match. Also the genuine EOLYS fluids have fuel treatments in it... cetane boosters and lubricity improvers and the PAT fluid does not!
Frankly REDEX (any of it) should NEVER be put into a fuel tank!! Most of it is paraffin which is not good for a high pressure fuel system. Most likely it will do nothing but if unlucky, it can push the wear to the point of failure. It's not to say all fuel additives are bad... it's just due to all the misinformation, 90% of fuel treatment products are absolute trash. You could even have a decent fuel treatment and a bad product... from the same manufacturer! (Redex have never made any good products though)
With DPF problems on a PSA, you need to work out what the problem actually is. If it's a driver issue, then you need to drive it on the motorway once a tankful of diesel. If it's a hardware issue, then you need to fix it. This could be a sticking injector causing rich burning, DPF fluid not working correctly, DPF pressure sensor not correct. EGR valve sticking open, wrong engine oil used. Work out what the problem is, then sort it out. On my 200k mile car, I've only had to replace the DPF differential sensor (£30) and the DPF (£130 but expected due to mileage).
Theres a couple of people in Exeter who have Lexia, and say they are willing to help people with problems, you could message them and see if they still have access to it. Most will do the diagnostics free or for a tenner or something. Unfortunately theres no way of telling if they are still active, but might be worth sending them a message on facebook
You need to get the DPF checked out, I thought that last time the injector went. If it's clogged on these engines it causes back pressure through the engine and will eventually cause the EGR valve, turbo and injectors to fail. If the turbo goes, then your injectors will seem like pocket change
If it's full of ash then it won't clear as that doesn't get burnt off during a regen, which is why it's important to get it checked. If you get a garage to look at it, tell them to specifically check the soot AND ash levels, and also the DPF fluid level.
These injectors have a lifespan of well over 100k if the engine is looked after, but obviously you have no way of knowing how it's been treated The rattle may go off, when you replace an injector they should be programmed in then they have to go through the learning stage and it can sound like a 50 year old tractor while it goes through that process, which takes ages, so wouldn't worry about that just yet (edited)
swallowgarage.co.uk/
saltersgarage.com/
theres a couple that claim to be specialists, obviously don't know how close they are, but considering your problem, I would rather use someone who knows what they are doing than someone who doesn't.
They might be a bit more expensive than a local garage but will be cheaper if they diagnose it properly and fix it, rather than guessing and you replacing injectors every few months. You might find they are cheaper for the injector you are getting done now too.
If someone won't use a third party part, that tends to be because they want to make that profit too, ask them for a price, I'll bet its more than £120 you can get one from ebay for. Just drive round some back street garages and ask, someone will do it for you.
There's no liability issues, you just sign the invoice to say customer supplied part and the fitter bears no responsibility for the part failing.
The only downside to buying your own parts, is if they are faulty you obviously have to pay for it to be removed and refit, whereas using a garage supplied part, you wouldn't get charged until they fit a working one. however, the chances of getting a brand new one that is faulty is quite small.
You really need someone who knows the engines to know the faults that can happen. I assure you the injectors end of life is not 100k if the engine is looked after.
If the DPF is blocked then what would usually go through it is pushed back through the engine, it causes back pressure which will eventually cause the injectors to fail, the EGR valve to block and the Turbo to fail too.
Ash does not 'blow out the car' at all, thats a mechanic who doesn't understand how a DPF works saying that. Heres a link explaining the process in a little more detail ukdpf.co.uk/all…fs/
I get what you're saying about not wanting a car with one, but pretty much any diesel car made from around 2010 will have one to comply with emissions law.
If it's working ok at the moment then just keep driving it, I get moneys tight at this time of year, but maybe after the MOT see about getting it sorted
It's this garage the one that changed the injectors previously, or did the previous owner have it done on the cheap by a mate? Only asking as most vehicles require the injectors to be coded to the car. If this not done, that could cause issues.
Also, you say it went into limp mode before, same injector. That's a bit suss. Maybe sensor or ECU issue.
Good luck, modern cars are a pain in the...* (insert body part here). (edited)
A faulty injector would help explain why your car was having regen issues. Lots more smoke would have been filling the dpf up much quicker and maybe even goosed the dpf up altogether. If 1 injector is replaced it is likely the others will also be ready.
Was the replacement injector new? Refurb? They usually also need coding to the car. I suspect they have put a new injector in but haven't coded it so it will be poorly calibrated and thus cause poor running.
Also if you're going to use additives then I'd recommend this. It's cetane booster that supposedly lowers the combustion temperature of the soot. Much better than any other additive you can use. It's 99% of the stuff you need rather than 0.1% like it is in other additives etc. (edited)
Pretty much this.
Can't see that redex will have done any harm, but equally doubt that it does much good.
The garage does need to have the correct diag tools to read and understand the codes.
When did the car last have a fuel filter change?
That wont sort the injector issue out though.
I still think what I said before is probably right. Injectors on these engines rarely fail without an underlying cause. For 2 to fail in such a short period for no reason is extremely unlikely.
Bearing in mind the previous problems you've had I would get the DPF ash levels checked, which you might have to do by taking it off the car. If you can find someone with Lexia local to you, they might be able to tell if someone has told the ECU the DPF has been changed, then compare that date to the condition of the DPF and see if it looks like it was. Having said that, I can't remember if Lexia has that information available, but I think it has. If someone has told the ECU it has been changed, and it hasn't, then it would fix the warning lights, but not the actual problem. The DPF is usually getting to end of life around the time the pat fluid needs changing. If it is clear, then I would be checking the EGR valve isn't clogged up, thats a pretty simple job for any garage. I did a lot of research into this around 18 months ago and changed my DPF at the time.
Unfortunately Peugeot have increased their prices recently, but it might be worth ringing them and paying for an hours diagnostics (£120 + VAT) explain the problems you are having and ask them to specifically check live data surrounding the DPF, injectors, turbo and EGR valve, and see what they come back with. They will at least know how to read the data.
The ecu will automatically clear certain codes if they're no longer a problem. When was the last time the fuel filter was changed?
With a faulty injector it wouldn't take long for the DPF to fill up. All the unburned fuel has to go somewhere and most of it will be trapped in the DPF! In the old days you'd get excessive smoke but not anymore, It gets trapped by the DPF which then creates loads of back pressure and problems! Maybe just keep running it, If another injector goes scrap it. In the meantime try and save for a petrol!
A blocked or perishing fuel filter can restrict fuel flow and cause injectors to block etc.. Might be worth changing it as it's a cheap thing to replace and might possibly save other injectors clogging up. I doubt that's your issue but might be worth changing.
You did get a message saying it was full?
P1490 - Particle filter - Filter overloaded
Seriously, get the DPF checked, I know these engines backwards, 2 injectors haven't gone after 100k if there isn't an underlying problem, and by far the most likely is the DPF. It 'may' be something else, but to check it is literally 2 minutes on a diagnostic and check the levels.
You can start by doing the much more expensive stuff first if you like, get the EGR valve taken off and cleaned, take the turbo off and check it, refurb it if required, replace the pipe when its put back on (very important), but they will cost you MUCH more than reading the DPF levels and checking the regen state.
If you don't find the underlying problem, then I guarantee you will be replacing the last 2 injectors before long, and redoing the ones you have already replaced. (edited)
They might not know what they are doing.
It is literally a case of plugging it in, going to exhaust, then reading live data, some diagnostic machines won't do it, but if they use a decent one like a SnapOn it will. It certainly shouldn't be any more, if you shop around you might get it cheaper than £25.
MUFC gives good advice too, although I don't agree the the DPF is expensive, you can get new ones on ebay for about £100-150 if you shop round and wait till theres a code, not a top make, but the cars 10 years old, it doesn't need a dealer part on it. It will cost you that much to get it cleaned, a new one will be better.
When it is fitted (or refit if you get it cleaned) they MUST go into replacement parts menu on the diagnostic and tell the car a new one has been fitted.
The other reason I think it's the DPF is, end of life is roughly when you have to refil the DPF fluid. Thats been done, so it is close. It is the ash content you want to be more concerned with, a regen will get rid of the soot.
The only other thing is, if the garage when doing the fluid also told the car the DPF was changed (to get rid of the light), then the levels will be wrong, but I would see what they come back with first.
Was it you I pointed towards specialist PSA garages in your area before? If not, what area are you in and I'll see if I can find someone local who actually knows what they are doing.
Couldn't find one for less than £500 for my last car but yes the Citreon/Peugeot aftermarket DPF will probably be more freely available and cheaper. A quick look on Ebay suggests less than £200 so that changes things. False economy to have professionally cleaned out then. (edited)
I got mine for £97 last year with a 20% code, quite possibly this one would fit, if not there are others around the same price. Also need a pressure sensor pipe that I forgot about which is about £30 max (but should be changed if the DPF gets cleaned anyway)
ebay.co.uk/itm…260
'julieallen' - The DPF Pat fluid was replaced in September 2019 and the soot content, DPF regeneration, memory cleared for the fault took place in November 2019. I don't remember you mentioning specialist PSA garages in my area - I actually live in Exeter, Devon. Thank you, both yourself and 'MUFC' have given me a lot of useful advice. I forgot to mention that they used a Bosch machine to read the error codes for my car.
Also, if I do end up having to get another DPF from same eBay, I'm not sure if my garage will fit it - only saying this, as once before a part needed replacing on another Citroen car that I had. I asked if I could go and buy the part (to see if I could get it cheaper) and get them to fit it and I was told that they couldn't do that - something about liability if they were to fit a part that they didn't supply themselves. (edited)
Thank you for the link, I will have a look at it. I normally have a bit of money saved up in the bank. However, I spent £2000 on the car, then within two months had to fork out around £1100 for the two fuel injectors, plus two new tyres (and a second-hand rear bulb holder that had burnt through on the indicator light). I was planning on going on holiday next year with my youngest son (haven't been away since Covid) but think that has all gone out of the window now, as think I'm going to have to dip into my savings to pay out for the MOT plus further fuel injectors in the future. Depending on the cost of the MOT, I might have to consider getting rid of the car before I have issues with the other two fuel injectors and I don't think that I will get another diesel. I'll keep things updated on this site though about the car. Thank you.
Thanks for the link about DPF's, an interesting read. I have a Ford with a DPF and I'd always assumed, wrongly it seems, that after a regen had burnt the soot, any remaining ash got blown out the exhaust. In fact I've always made a point of occasionally doing some hard acceleration, thinking that the sudden rush of exhaust gases would help blast the ash out and keep everything clear. Obviously that strategy was a complete waste of time, and fuel, and in reality ash remains trapped in the DPF forever.
I presume that does mean though that any DPF, no matter how well looked after, will eventually clog with ash and fail?
Effectively its a service item, just like an air filter. (edited)
Yeah, pretty much, thats why they tend not to be covered by warranties.
As regards the DPF light coming on (over the past few months), that has stopped again since driving the car twice a week down and up the motorway in a lower gear than needed (for a regen to happen). Over the past several months, I have added a bottle of DPF cleaner and that doesn't seem to be causing an issue with the car. The last time that one of the fuel injectors went, after it was replaced, I did add a bottle of the Forte fuel injector cleaner to the car (which the garage recommended to do).
So far, I have had no more issues with the remaining two fuel injectors, although I am expecting them to go at some point in the near future. Due to the car breaking down twice on the motorway because of the fuel injectors going, I now only drive in the first lane, if possible, especially as it is very dark when I am out. It might sound a bit silly to do, but if they are going to go, I'd rather it happened whilst I was driving in the first lane rather than one of the other two. When my injectors did go, the car suddenly dropped down to only about 15 mph, which is not something that I would want to happen if I was in lanes 2 or 3, as it could be very dangerous.
Yes, it won't be long before the other injectors go. They are very expensive. I'd get rid. Lots of short journeys then get a petrol car.
True, Greta Doomsberg won't be happy though (edited)
Did you not Google how to re-gen it when the light came on? I've never had issues with a DPF but a few friends have, they usually take them on the motorway at a set speed for something like 20minutes to re-gen them.
I know a friend with a Polo had to get a new ones as his was knackered, cost him something like £800
I never trust these stupid additives as they could cause more harm than good.
Maybe play dumb and don't mention the stuff you've used to the garage and just see what the outcome is, if you tell them you've been adding stuff they could say this is broken and this is broke...
No you can’t, Eolys and adblue use there own tank.
Doing so would kill the car.
Newer diesels use adblue, like my Peugeot 5008.
I’ve driven over a million miles in diesel cars over the last 32 years, 50,000 a year in old 228 and 418 rover diesels.
They had 100,00 miles on them when I got them, I have never replaced an injector on any car I’ve owned.
I go on the motorway one a month on a Sunday morning at 7am. Get up to speed set the cruise and drop a gear until I’m hitting 3000 rpm. Sit there for 20 mins and then turn around and do the same back.
Im a low milage driver, 15,000 in 5 years and mostly local, not good for diesel.
Ive noticed that my car has regenerated twice, only as when I got out the exhaust was ticking as cooling down and could smell the heat.
I add a miller’s diesel additive every second tank, I don’t know if it works but is my choice.
The best every additive was Tec2000, can’t get it now.
One in the tank and one neat in the fuel filter.
Would produce clouds of black smoke for the first 5 miles them next to nothing. (edited)
No but it will stop it clogging up because the injector fault is stopping the regen
What car and year is it? (edited)
Did you do anything I suggested below?
hotukdeals.com/com…213
I still think this is related to your DPF problems, and the garage you are using doesn't have a clue what they are doing.
I did put a bottle of the Redex DPF cleaner in several weeks ago now, and since then, the car has done a regeneration and the error message about the DPF clogging has not come up (not even when it broke down the other night) - I have also been doing two motorway round-trip journeys of 40 miles on a Sunday and 66 miles on a Monday (on top of my usual local drives to work, school, shopping etc). Does a DPF cleaner only sort out the filter issue but not clear any blockages in the fuel injector then (the garage did say that it was clogged)?
I have gone over the invoices passed on from the original owner and two years ago it says that they had 1 unit of PAT FLUID FUEL BORNE added at a cost of £56.53 (due to their DPF additive warning light being on it says). I've googled the part number and it appears to be a 1L bottle of it, not a bag, so that does mean that my car uses the EOLYS system I think?
If it is using PAT fluid, am I right in thinking that I will not need to use the REDEX DPF cleaner as well (which I have recently used once)? I've noticed that Redex also do a diesel system cleaner for fuel injectors - would it be worth me using one of these now regularly as well now? I only bought the car (Citroen C4 Picasso, 2011 reg) in September and did read up on it's MOT history - it passed 7 times out of 10 years with no work needing doing for the MOTs, so thought it would be a good buy. The MOT is due at the end of January, so depending on that, I might have to consider if I am going to keep it or not. At the moment, I'm just thinking that if two of the four injectors have gone in a matter of only 2 months, the others are going to go as well, and it wasn't a nice experience driving in the dark down the motorway when it did go. It's also turning out to be an expensive buy. I have had diesel cars for years and I have never had to have a fuel injector replaced. (edited)
I have read that the lifespan of a fuel injector is typically between 50,000 - 100,000 miles - my car has now done nearly 102,000 miles. I paid £2000 for this car in August and since then I have been billed in total around £1000 for two new fuel injectors and two new tyres.
The car is now back and it was the 1st fuel injector that needed replacing - last time it was the 2nd one (my car has 4 of them) - the garage have also printed off the fault codes for me, which now looking at, am a bit confused by.
In September, the following codes appeared (I did need to replace the rear bulb holder as part of it was burnt):-
P0265 - Injector cylinder 2 - short circuit
P0461 - Fuel level signal - CAN signal not OK
P1403 - Supplementary heater - Short to +/ground, or open circuit
P1404 - Supplementary heater - Short to +/ground, or open circuit
P2291 - Rail pressure - Press. build-up on startg. not poss.
P1621 - Engine control unit - Level 2 monitoring fault.
A few days ago, the following codes appeared (when taking it in for an engine/injector issue):-
P1490 - Particle filter - Filter overloaded
P0262 - Injector cylinder 1 - short circuit
P0113 - IAT sensor - open circuit/positive short.
I'm just wondering what happened to the other codes that appeared in September - as they are not showing on the last reading?
I did mention to the mechanic at the garage that about a month ago, I did add a bottle of DPF cleaner and that the DPF clogging message (that came up about 3 times in a short period of time) has not come up once since. I also thought that a regeneration had taken place after using it, whilst doing a good run down the motorway in a low gear at the speed recommended for a regeneration to take place). The mechanic then said that it was possible that the P1490 Particle filter overload code had not cleared from the system even though it sounded like a regeneration had taken place - do the codes clear automatically, or does the garage have to actually clear them then?
The outcome is that injector cylinder 1 has now been replaced. I was given information about perhaps using the Forte Diesel Specialist Injector Cleaner to see if it would help the two remaining injectors, as they were not looking that great either apparently (I added a bottle of it this morning to my car). The mechanic also suggested driving up the motorway/slip road in a low gear, etc, at several intervals to try to clear any issues with the DPF.
They have also said that there is a rattle/knocking from the engine, which I have not actually noticed myself. I was told that this could have been caused by the fuel injector and that the noise could disappear after having it replaced and perhaps using an injector cleaner, so it's going from bad to worse - I think they said that it is known as Diesel Rattle in the trade?
I'm not actually now in a financial position to just go and replace the other two injectors before they go, especially as my MOT runs out on 29th January. I'm hoping that the two injectors actually hold out before the MOT, then I will put the car in for it's MOT and see what the outcome/cost of that is first. Part of me wants to just get rid of the car as I'm now going to be worrying about driving it around, especially up the motorway and back in the dark (which I have to do twice a week), but I'm not able to afford to just go and buy another one now and scrap this one (that would be £3000, including the repairs, wasted).
Thank you for the advice. However, wouldn't it show/flash up on my dashboard that the DPF was full? - Apart from the message about the DPF being at risk of clogging around a month ago, nothing is now showing on my dashboard to say that there is an issue with it, but I do understand what you are saying about ash not being able to clear from the DPF. I'm assuming that a proper DPF clean to remove the ash would be a lot cheaper than getting another DPF?
I've just checked the paperwork/invoices passed on to me by the previous owner. They had the fuel filter changed as part of a service in August 2018, however, the car doesn't appear to have been driven at all in 2020 according to the mileage history. Looking at their last invoice, for 29/1/21 when the car went through the MOT, it says that a service was carried out again, however, it only says that the following were done for the service (not sure if they forgot to put down fuel filter on the invoice?) - air filter, oil filter, oil 5W30 C3.
I will call the garage again and ask them about reading the DPF levels and checking the regen state. If it literally takes only 2 minutes on a diagnostic, I don't understand why the garage didn't check this at the time - is it a different machine that they use to the one that reads the error codes then? I got charged £25 for the codes to be read on one of their machines, so would it be about the same price to read the DPF levels? Thank you. (edited)
No, Some diagnostics machines will show the ash content as well as how full of soot it is. The light will only likely show when the soot content is over a certain percentage, Usually around 90%ish as a rough figure. Then it's demanding you do a regen etc.. or it's displaying a warning that regen has failed or other fault etc
The ash content will increase after every regen and it will build up over the lifespan of the DPF, That'll mean that the DPF will eventually be full of ash. So it'll regen more frequently as there is less space in the DPF.
You could have your DPF removed and send it away to be professionally cleaned out. They'll usually come back with a before and after flow rate printout. Usually costs about £100-£200. There are some that offer in situ DPF cleans but I doubt they'd make much difference. You could also remove and jetwash it out or chemically clean it. There are plenty of Youtube videos of them cleaning them out etc..
Once you get it back though you might need it re-calibrating with the car. The cars ecu might think the ash content is higher than it is otherwise. Causing your car to regen more frequently than required.
Another option would be to have it smashed out and remapped. It is an MOT failure if they can see any tampering and morally it's probably wrong to do that due to the emissions etc Probably cost you £150-£300. You'll likely get much better performance too.
A new DPF would be very costly and a second hand one could be worst than the one that's already on it.
I've googled these people in Exeter and it says that one of them is a friend of my son, although I don't actually know the man personally. Thank you.
ah well, thats even better, hopefully he can at least read the data for you and see what the levels are in the DPF