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See post #84 on this thread.
Thanks will try to have a look at mine later. I have been running a remap on mine for a while now and my regens are currently between 125-160 miles depending on how hard I drive so I'd be interested to see if it's causing excessive carbon build-up. Been monitoring the variou pm pid's with forscan and have noticed my pm_acc & dsd values were both around 5.4 when I switched the car off this morning and the pm_gen was just under 4. Is that normal or a symptom of an issue?
 

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Thanks will try to have a look at mine later. I have been running a remap on mine for a while now and my regens are currently between 125-160 miles depending on how hard I drive so I'd be interested to see if it's causing excessive carbon build-up. Been monitoring the variou pm pid's with forscan and have noticed my pm_acc & dsd values were both around 5.4 when I switched the car off this morning and the pm_gen was just under 4. Is that normal or a symptom of an issue?
See also post #67. Seems DPF can be partially clogged
 

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@javier.g I believe I have a similar engine as yours (2.2 D 175 hp from 2016).
My car has 127k km and I use it for mixed roads. In the last 2 years the reg distance went from 300+ km to less than 80km to till now I tried different things. I still have to understand the cause but I suspect on of these 4:

1. non-Mazda service put wrong oil
2. I put the Premium Diesel for 2 tanks in July this year (shame on me) because it does not help the Skyactive D engine
3. The DPF is close to it's end of life (ash filling that is not burned by the regenerations)
4. Many in town driving due to Covid restrictions

The actions I did after it are the following:

1. Cleaned the carbon from the intake/EGR/MAP at Mazda Workshop (it improved the engine response and power)
2. Did a 3000+ km trip mainly highway and I was able to see only once 300 km between regenerations
3. Used the STP Diesel additive for the DPF cleaning - it helped to increase maybe the reg interval to 100-110 km
4. Used hydrogen intake cleaning - it reduced the consumption average from 9 l/100 km toward 8 l/100 km (example: at 90kmh it shows 5.2-5.3 l/100) but I did not improved the regeneration intervals
5. Used the Wurth DPF cleaner - it works by spraying it trough the input DPF pressure tube: it improved the reg interval to 150 km in average
6 Did a more complex cleaning of the DPF at home without removing using 3 step cleaning for both soot and ash, as the first needs a detergent (pH basic) and the second needs an acid (pH acid) that I was inspired from this guy ttps://www.youtube.com/watch?v=Vsicb0LsIiQ , using a pressure gun with the liquid can where I sprayed in the DPF in sequence (2 L of 50% dishwashing liquid, 2 L of 10% caustic soda, 4 L of clean water, then 2 L of NaCl 10% acid and other 4 L of clean water as final step)

Now I have 150-200 km regeneration distance in average but I want to understand it the cause can be the injectors or other (DPF/EGR).

My current ForScan DPF values (DP_DPF pid) after a reg are:
  • 0.2 kPa at Idle (800 rpm)
  • 0.9 kPa at 2000 rpm (car stopped in Parked mode)
  • 4.9 kPa at 3000 rpm (car stopped in Parked mode)
Just before a reg are:
  • 1.2 kPa at Idle (800 rpm)
  • 9 kPa (circa) at 2000 rpm (car stopped in Parked mode)
  • 25 kPa at 3000 rpm (car stopped in Parked mode)

May I ask you please what are your values right after a regeneration?
As my only concern is the 3000 rpm value, because if this is a good reading, it means my DPF is good and I have to look elsewhere for the DPF Fast Filling problem ...

As for other guys who changed their injectors and still have less than 100 km interval between regs, I strongly suggest you to clean professionally the DPF by removing it and remounting it, especially if you have 100k + km onboard as the car must do between 250-400 km depending of the driving style.
 

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Have you considered getting the core of the DPF removed physically and an ECU remap so that ECU knows the DPF has been removed?

This is illegal in some countries but if done properly will not be seen when your car is inspected. It will also depend on the strictness of diesel emissions tests in your country. In the UK this is easy to pass.

Usually, they open the DPF can and remove the filter element and replace it with straight pipe which removes the problem for ever. At the same time you could always go for an ECU power upgrade.
 

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Hello @zdarova mine is 2.2D 150hp from Dec'15.
Seems your DPF is quite clean now. After the washing did you perform an static DPF regeneration? It will help to eliminate any residual particles.
After doing that maybe resetting the DPF learned values will also help.
I can show you the values of my last trip:
 

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Have you considered getting the core of the DPF removed physically and an ECU remap so that ECU knows the DPF has been removed?

This is illegal in some countries but if done properly will not be seen when your car is inspected. It will also depend on the strictness of diesel emissions tests in your country. In the UK this is easy to pass.

Usually, they open the DPF can and remove the filter element and replace it with straight pipe which removes the problem for ever. At the same time you could always go for an ECU power upgrade.
Not in some countries, in the whole EU.
And the possibility of passing the technical inspection with a downpipe is really low as, at least in Spain, the PM are measured and compared to the homologated values.

Not the same case with EGR's that can be done remapping and you don't have to worry about technical inspections, as NOx are not measured. Closing them you will get an increase in regeneration distance and eliminate the cause of carbon build up in the intake.
 

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Gracias @javier.g , I will do a dpf reset using the usb adapter and the Windows version of Forscan.

I see that your values are quite good to be at almost 300km and not right after a regeneration.

After the cleaning I did not do a static regeneration but it did a automatic one on the road the next day, a lot of white smoke went out.

@Percy247 , the dpf is not a option for me because of what javier said...
 

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Emissions laws are good news for the environment but bad news for people driving high mileage diesel cars.

To keep a modern Euro 6 diesel car running properly you need to be driving 20,000 miles (32,000km) a year, using good quality diesel and servicing it correctly. If you are not doing all of the above then DPF, soot build up and EGR problems will happen sooner rather than later.

The DPF, whilst reducing NOx, increases fuel consumption by 5-10% over a tank of diesel and the EGR just fills the engine with soot. This is not helped by the 1.5 Skyactiv-Diesel not performing passive DPF regens.

If I was going to delete the DPF, I would source a spare one to modify and keep the original in case I needed to put the car back to stock.

I may well look into an EGR delete. I guess the car would warm up slower and fuel economy would be worse on short journeys.
 

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Just checked my car with forscan and it currently seems to be regenerating every 124 miles (198km) which is about 5 times every full tank of diesel. Average journeys are only 10-15 miles (16-24km) so I have to watch the instant mpg to avoid getting into a cycle of incomplete regens. Noticed it today and kept driving for another 5 minutes until it had completed. Next year I will be trading it in for a petrol car because we are not driving far enough to justify keeping it.
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DP_DPF @ 2000rpm is 0.8 to 1.1kPa
@ 3000rpm is 1.6 to 3.0kPa

The figures are min and max and the number changes at constant revs. What does this tell us? This is for the Mazda 1.5 Skyactiv-Diesel engine.
 

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From my findings, having the DP_DPF value bellow 5-6 kPa for 3000 rpm (bot after and before regenerations) means that the DPF is relatively clean.
In my case the DP_DPF values after the reg is quite low at Idle (0.2 kPa) and at 3000 rpm is around 6 kPa.
But before just the regeneration, the DP_DPF are 1.2 kPa at Idle and 25 kPa at 3000 rpm.
Therefore my DPF is not completely clotted, but also not very clean, as I hardly arrive at 150 km between regenerations.
 

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DPF regeneration depends on how much "load" (i.e. fuel consumption) the engine normally works at. It does not depend on high/low rpm dirving habit. For example, in my experince: highway trips, 130-160 km/h, engine works at 2.200 - 2.600, 6th gear, average fuel consumption is 6-7 L/100KM, engine load is quite "serious" and DPF regeneration occurs every 290-300 km. Interstate roads trips, 70-90 km/h, 4th/5th gear, average fuel consumpion 4-5 L/100KM, engine load is mild and DPF regeneration occurs every 360-370 km. @gazbo: mazda's DPF regeneration system is an active one (not passive) and is based upon the exaust gases differential pressure mechanism (differential between exaust gas pressure "before" the DPF and "after" it): putting it simple, when the differential pressure exeeds a predetermined value, it means that DPF is "full" (due to the particles trapped in it, exaust gases come out from the DPF at a lesser speed than the one at which they enter it, and there are 2 sensors which constantly mesure these speeds) and then the engine control unit (ECU) forces the DPF regeneration, "cleaning" all the particles by turning them into CO2 by means of very high temperature and fuel (chemical reaction).
The differential pressure sensor is what triggers the Regen, it doesnot measure velocity of the gas but the pressure as you rightly said earlier in your explanation. This is the sensor which measures the dp. If you have too many regens you get P243C.00.2F code come up. The sensor islocated to he left of the engine up against the firewall bolted to a bracket, rubber tubes connect between the sensor and steel tubes coming offthe DPF. There is another exhaust sensor that actually measures the pressure of the exhaust. With the aid of Forscan and a OBD reader you can see the readings from these sensors, including various exhaust temperatures in the system, plus the number of miles/km since the last regen. You can sometimes miss on the instaneous fuel consumption if its hilly.
 

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