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Mazda CX-5 - DPF Regeneration - Diogob

Hello everyone,

So i have a Mazda diesel 2.2 that has broken down and i found out that the problem was from the DPF, im wondering as i get it fixed should i just change to a Petrol Car? Or is there a way to be safe and the problem not hapenning again? I was driving mostly in town and country side road on a regular speed, i have an option to go to work by a motorway for a few miles will that help?

Mazda CX-5 - DPF Regeneration - Ian D
How many miles has the car done and what is your annual mileage? How long is the motorway part of the run if you took it?
Mazda CX-5 - DPF Regeneration - mcb100

Extract from Mazda's own manual:

The diesel particulate filter collects and removes most of the particulate matter (PM) in the exhaust gas of a diesel engine.

PM collected by the diesel particulate filter is cleared during normal driving, however, PM may not be removed and the diesel particulate filter indicator light may illuminate under the following conditions:

  • If the vehicle is driven at 15 km/h (9 mph) or less continuously.

  • If the vehicle is repeatedly driven for a short period of time (10 minute or less) or driven while the engine is cold.

  • If the vehicle is idled for a long time.

With Multi-information display

When “Soot Accumulation in DPF too high” is indicated

The particulate matter (PM) cannot be removed automatically and the amount of collected PM reaches a specified amount.

After the engine has sufficiently warmed up (engine coolant temperature of 80 °C (176 °F) or more), depress the accelerator pedal and drive the vehicle at a speed of 20 km/h (12 mph) or more for about 15 to 20 minutes to eliminate the PM.

When “DPF malfunction” is indicated

Contact an expert repairer, we recommend an Authorised Mazda Repairer.

Without Multi-information display

When illuminated

The particulate matter (PM) cannot be removed automatically and the amount of collected PM reaches a specified amount.

After the engine has sufficiently warmed up (engine coolant temperature of 80 °C (176 °F) or more), depress the accelerator pedal and drive the vehicle at a speed of 20 km/h (12 mph) or more for about 15 to 20 minutes to eliminate the PM.

When flashing

Contact an expert repairer, we recommend an Authorised Mazda Repairer.

Refer to Warning/Indicator Lights (Search).

Mazda CX-5 - DPF Regeneration - Metropolis.
Fix as quickly and cheaply as possible and then get rid. If you like the CX-5 then find a petrol version
Mazda CX-5 - DPF Regeneration - FP

More recent Mazda diesel engines may indeed be more reliable than previously, but it's an unknown, and the OP should be aware of Mazda's poor record of reliability.

A lot of us here - myself included - would not touch a Mazda diesel. When I bought a CX-5 a few years ago I made sure it was the petrol version. In contrast with diesel engines, Mazda's petrol engines have an excellent record of reliability.

However, there's no denying the car benefits from the grunt of diesel. You need to thrash the petrol version a bit if you like to make progress. Fortunately my driving style is pretty sedate these days.

Mazda CX-5 - DPF Regeneration - gordonbennet

Yes a motorway run would help, got to be 20 mins or so once the engine is hot to give a fair chance of regenerating.

Also, ignore completely the recommended oil change intervals, failed regens dump fuel into the crankcase, not only will diluted oil cause rapid bearing wear you are increasing the possibility of the engine consuming its own sump mixture and self destructing.

Regular oil changes are cheap if you bulk buy oil by 20 litres at a time and the same with filters and DIY this simple operation...might be an idea to send a sample of the first drain for analysis give you an idea of oil dilution is a problems for you...i'd be suggesting no more than 5k oil changes for the time being and see how you go, maybe get a second analysis at 3k and see how the new oil and new travel regime is working out.

Doesn't need to be Gucci oils @ £50 for 5 litres (and a lot more the way a dealer workshops charges), look around and you'll find good quality suitable synthetic oils from the likes of Exol or Westaway costing you no more and often less than £20 per 5 litre when bought in 20 litre drums, jus check what your engine requires and make sure the oil covers it.

If you take sensible precautions and make sure the car gets a decent run regularly i don't see any reason why you couldn't carry on with this car for a long time yet, i wouldn't be getting shot of it until i'd tried altering usage and maintenance and see how it goes.

Edited by gordonbennet on 19/09/2020 at 10:07

Mazda CX-5 - DPF Regeneration - Diogob

I have done around 2/3k miles since i bought it, the day it broke down i didn't warm it up enough and just drove off,my normal commute time is around 25 minutes with town and countryside driving, if i go on the motorway it may be 5/10 miles maybe not more than that.

Yes i think to be safer i will have to get rid of it and get a petrol car, the Mazda diesel have a bad reputation for this issue, when i bought the car i wasn't aware of this its a lesson learnt

Before it broke down sometimes i would smell some burning smell i thought it was from the rear brakes as the smell was coming from that side, could it have been the DPF? I did the full service on the car at a main dealer and mention the smell and to change the brake pads/discs if needed but they said it was fine,afterwards i continued smelling it sometimes

That seems a good option gordonbennet but at the same time i dont want to risk it?

Edited by Diogob on 19/09/2020 at 17:19

Mazda CX-5 - DPF Regeneration - gordonbennet

The burning smell was probably regen in process, sounds like you stopped it mid regen more than once hence it blocked the DPF.

Not blaming you here, if some bod not wearing a coco the clown outfit in the design room had come up with a simple warning lamp** on the dash when a regen was due/needed/underway i'm quite sure half the issues people have with these things would not be.

As its had several failed regens now, if you decide to run the car for a time i urge you to change the engine oil as it has more than likely gained some fuel mixture.

** one some lorries we can call up the level of DPF ash content on the menu, all lorries i've driven with DPF you get a warning when a regen has started and can cancel it if its going to be dangerous to allow it to continue, and another button you can press to perform a static regen where you find somewhere safe to park for 30 mins whilst the engine goes to fast idle and cleans the DPF...car makers seem to assume their buyers are cabbages, why isn't such a system available via the on board menu for cars?

Edited by gordonbennet on 19/09/2020 at 18:14

Mazda CX-5 - DPF Regeneration - daveyjp

They don't do it on cars because imagine the reaction when you tell a buyer. 'every time that light comes on you need to drive the car, or leave it idling until it goes off'.

Mazda CX-5 - DPF Regeneration - gordonbennet

They don't do it on cars because imagine the reaction when you tell a buyer. 'every time that light comes on you need to drive the car, or leave it idling until it goes off'.

Fair, but they should have built the system in so buyers with a clue could access the facility, instead of which in true one size fits all style they must have assumed because some hadn't a clue that all buyers could not compute.

I'm sure i heard John Cadogan having a pop at Toyota because they ended up fitting a manual regen facility on 2.8 Diesels (Prado/Hilux) in order to help with regen issues...how many drivers on here that would make such a difference to in their choice of vehicles if they knew that in the event some of their motoring, ie at times like this, being unfriendly to DPF they could take some positive actions.

Edited by gordonbennet on 19/09/2020 at 18:33

Mazda CX-5 - DPF Regeneration - Diogob

That might have been the issue, normally i would smell it when i reach work, not knowing what it is and not being an expert i was just turning off the car and wondering what it would be, i would definitely appreciate if the car would tell me that the regeneration is on for example

The car has broken down due to not knowing anything about it, and the DPF got blocked, the Mazda Dealer told me i need a new engine costing around £9000

Mazda CX-5 - DPF Regeneration - gordonbennet

The car has broken down due to not knowing anything about it, and the DPF got blocked, the Mazda Dealer told me i need a new engine costing around £9000

Bit more going on here than a DPF blocked by a few failed regens.

Mazda CX-5 - DPF Regeneration - Diogob

The car never showed any warning light or signs of something wrong apart from the burning smell, and out of nowhere coming from work it lost the power, and a warning light came on mentioning low oil pressure, the engine was rattling alot after

When i got the car it needed to be serviced, so could the DPF been semi blocked already? Hqrd to know

Edited by Diogob on 19/09/2020 at 21:43

Mazda CX-5 - DPF Regeneration - gordonbennet

The car never showed any warning light or signs of something wrong apart from the burning smell, and out of nowhere coming from work it lost the power, and a warning light came on mentioning low oil pressure, the engine was rattling alot after

That suggests to me excess fuel dumped by multiple failed regens and lack of suitable oil changes when this happens has done the damage one would expect, or it might have overheated, or the timing's slipped or any one of lots of things could have happened, would have helped if you'd said the engine had low oil pressure and sounded like a bag of spanners in the first place.

Used engine time if you can find one.

Mazda CX-5 - DPF Regeneration - Diogob

So i have been looking at DPF cleaning/regeneration and found a DPF cleaner that lower the temperature the soots burn at, meaning it will burn driving normally around town without need to drive on motorways, they recommend to do this every 2/3 tanks do this actually work??

Mazda CX-5 - DPF Regeneration - gordonbennet

So i have been looking at DPF cleaning/regeneration and found a DPF cleaner that lower the temperature the soots burn at, meaning it will burn driving normally around town without need to drive on motorways, they recommend to do this every 2/3 tanks do this actually work??

Can't see it fixing a blown engine that the garage have condemned as needing replacement.

Mazda CX-5 - DPF Regeneration - Diogob

Yeah what i mean is, after getting the engine fixed/replaced.

If i change the oil every few thousand miles and with the DPF cleaner additive added to the fu el tank as recommended should it solve the problem of it getting blocked again?

Mazda CX-5 - DPF Regeneration - gordonbennet

Yeah what i mean is, after getting the engine fixed/replaced.

If i change the oil every few thousand miles and with the DPF cleaner additive added to the fu el tank as recommended should it solve the problem of it getting blocked again?

PSA group came up with a catalyst (EOLYS i believe it was called) which is a small tankfull of the product, small amounts of which are automatically added to the fuel when the tank is refilled and to be fair their DPF's have been little trouble compared to some others, but then PSA were in at the beginning of fitting Diesel engines into cars so should know a thing or two.

I have no idea if the product you are considering will work, you would be wise to change oil more regularly, yes, and try to modify your driving to help, and try to spot when your car is in regen mode (others will be able to advise better how to tell) so you don't stop the engine mid cycle will help enormously.

How much simpler life would be if they'd just put a light on the dash to let you know regen due or commenced.

Mazda CX-5 - DPF Regeneration - DavidGlos
Accepting that I have a different car, clues that the DPF is regenerating on my Golf GTD include:-

Higher instantaneous fuel consumption
Stop/start becomes inoperative
Raised tickover speed
Lumpy tickover
Engine cooling fans remain on if engine is stopped. If you stop the engine at that point, best to fire up again and keep driving for 10 minutes, in the hope it finishes the regen cycle
Mazda CX-5 - DPF Regeneration - RT
Accepting that I have a different car, clues that the DPF is regenerating on my Golf GTD include:- Higher instantaneous fuel consumption Stop/start becomes inoperative Raised tickover speed Lumpy tickover Engine cooling fans remain on if engine is stopped. If you stop the engine at that point, best to fire up again and keep driving for 10 minutes, in the hope it finishes the regen cycle

The symptoms vary - apart from the last one if the regeneration hasn't finished, I get none of those on my VW Touareg

Mazda CX-5 - DPF Regeneration - DavidGlos
Accepting that I have a different car, clues that the DPF is regenerating on my Golf GTD include:- Higher instantaneous fuel consumption Stop/start becomes inoperative Raised tickover speed Lumpy tickover Engine cooling fans remain on if engine is stopped. If you stop the engine at that point, best to fire up again and keep driving for 10 minutes, in the hope it finishes the regen cycle

The symptoms vary - apart from the last one if the regeneration hasn't finished, I get none of those on my VW Touareg

You’re lucky you don’t get the lumpy tick over one. Feels like it’s shaking itself to pieces. I’m glad mine’s a company car and that any bills are paid by the lease company. No way I would want it as a private motor with such a poorly resolved DPF installation. It’s an early Euro 6 (pre SCR/AdBlue) and it feels like it only just meets the emissions standard without SCR and would be better resolved with it!

Mazda CX-5 - DPF Regeneration - DavidGlos
The DPF installation on the wife’s 2011 Euro 5 Golf TDI is more akin to the Touareg and far better than on my later GTD!