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If you notice that regen has started (high consumption, exhaust noise, i-Stop engine indicator), just downshift a gear or two. When engine revs over 3000, regen is done in less than 5 minutes.
 

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It's odd...for the past few months I have not noticed my car doing an active DPF regen. Previously, it seemed to do it once per tank.
Car has 36,000km.

I always thought that if you did enough highway driving (as I do), the exhaust should get hot enough to regenerate the DPF ( a passive regen) without injecting the extra diesel into the exhaust (active regen). Maybe my car has just started working correctly?

Does anyone else do lots of highway travel ? If so how often do you notice an active regen?
 

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I notice in my normal driving that I get a regeneration roughly every 250km. I do very few trips longer than 12km. However when I am towing the caravan and the engine is working hard, I do not notice any regeneration happening which seems to support your "passive regeneration" with a hot engine theory.

When I notice that regeneration is in progress I try and keep the revs above 2000rpm, In fact when driving home from work I have a short motorway drive where I can do 120kph, followed by a longer part restricted to 80kpm, it is here that regeneration often starts. I have also noticed if I change down to 4th gear (2200rpm), regeneration finishes faster and is usually ready before I leave the motorway.
 

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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).
 

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I'm not doing exact stats, but for me DPF regeneration is happening every 200km/h. I'm doing aggressive and city driving mostly. If you are usually driving on the highway and don't have the fuel monitor app on the screen always you might just miss it. However, since I'm driving in the city I always notice it:
- higher RPMs when idling
- instant higher fuel consumption that lasts specific period of time without changing the style of driving
- deeper exhaust noise (I wish I had that always)
- gas pedal acts a little bit differently (I wish I had that by default)
- the engine blue shadow is not shown in the fuel monitor app
- i-Stop doesn't work when turned on and the engine is not cold, and battery and A/C icons are with blue shadow
@owner: DPF definitely depends on the engine load (which translates into fuel consumption) as you said.
@Jukkeli that might be a good point there. I'll definitely try it and see the time it takes when holding up RPM around 3K, which is kind of hard when driving in the city. If you start giving it too much stress or just let it idle it will actually take a lot longer, even up to 30 minutes. My usual DPF regen takes about 10-15 minutes while driving in the city.

For everyone that's interested I'm just giving an example here: If you are accelerating from 0 to 60km/h as quick as possible by shifting from 1st to 4th gear before 2000rpm you are actually putting more load to the engine than driving 130km/h in 6th gear for the same time.

So in theory and statistically how often DPF regeneration will happen depends on your fuel consumption. Usually it happens once in 15-20 liters of fuel consumed, however it's not very precise and constant and the ECU actually tries to follow your driving style and starts up DPF regeneration when your driving style matches the ideal conditions to regenerate DPF - which might be just incorrect and you can change your driving style or you can even turn off the engine right when it starts. Then it will continue DPF regeneration instantly after you start the engine (if the temperature is above the minimum at a few sensors).

Simple stuff, huh. Not really. It happened to me that the car didn't want to start for about two hours because the exhaust got overdosed with fuel (just a wild guess). I was driving normally, DPF regeneration was started (I didn't notice it), then I started pushing the car to the limit (fuel consumption went a lot high over 20 l/100km), then drove about 5 mins normally (fuel consumption showing over 10 l/100km), and then just turned off the engine and went to the market. Car didn't want to start afterwards. I tried a few times only as I didn't want to kill the battery, but it might have started if I continued trying, however I just left it idling and then after about two hours it just worked. Why this happened is unclear and there were no error codes at all, but there might be a situation that is just not handled properly. I've intentionally tried the same scenario many times and didn't manage to break it again. No explanation from Mazda officials about it.
 
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Hi,

I can confirm that the 2.2 diesel does DPF regens more less every 250 kilometers.

I have a obdii reader and data from the computer gave me a total number of regens done so far. Compared to the total mileage done - it game me an average of 250 km more less.

The thing is, that I don't thing this car does passive regens. It seems it does active ones regardless of exhaust temperature. The obd scanner shows me that at around 140 km/h on 6th gear you easily reach 400 degrees celsius on highways, but it probably is not enough to burn the soot. I have driven my car even faster than that but if there were passive regens, they would not count to the total regens done, would they?

Anyway, regardless of your driving style, it seems that active regens are done every 250 km.
What I can also confirm is that if you give the car a good spin every now and then, the regen is unnoticeable. I have only noticed 1-2 regens in the city and only because istop was not functional.
 

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Here is my super advice tried out yesterday. If you notice dpf regen has started, keep the revs steady at around 2200-2500 rpms until it finishes. It took around 6 minutes for mine to finish from start until end (cruise control engaged).

I had a problem with a regen at around 3k rpms or more, when the engine speed was not steady and accelerating and braking. In fact, because of this the regen took much longer and decreased mpg significantly. On a negative note, I think this one increased oil level a bit.
 

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hi,
Anyone with idea why mine Mazda 3 2.2 Skyactiv-D is regenerating DFP every 130-140 km. I'm driving mostly extra urban ~100 km/h.
Another thing I noticed is increased fuel consumption alongside (without regen happening)
90 km/h Cruise control - ~6L/100km
120 km/h Cruise control - ~8L/100km

So far I did replaced MAF, all filters, Vacuum Pump, and cleaned carbon from intake (all done by Mazda official service)

and I still get high fuel consumption and DPF regen in short periods.

Help is much appreciated. Thanks
 

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Guys I have a problem then.. When I go on highway trips my consumption ( I figure now its dpf) jumps too high and too often..
If I go to 280km trip i get at least 4-5 times un-normal consumption..
Engine is 2.2 s 150hp, 164k km..

@Yonef we have same problems..
 

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Does anyone know (will share knowledge) about why DPF regen getting often and often.
Mine started at about every 140 km, and 6000 km later on, it is now regen every 80 km.
I've check around all and this is common problem, and there is a solution, but nobody said what it was. I found few posts over the internet that taking the car to Mazda service center sorted the problem, but they don't mention what was the solution.
I took mine to Mazda service center and they had no idea how to fix this and what is causing it :(

Please, if anyone had an idea what needs to be done, share the solution.

So far I did:
1. Forced long regeneration of DPF (performed by Mazda personnel)
2. Checked all Diesel fuel injectors (all worked fine)
3. Used several additives cleaning DPF ( DPF ware factor reported by Mazda software is about 7% - excellent)

none of the above worked.
 

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Does anyone know (will share knowledge) about why DPF regen getting often and often.
Mine started at about every 140 km, and 6000 km later on, it is now regen every 80 km.
I've check around all and this is common problem, and there is a solution, but nobody said what it was. I found few posts over the internet that taking the car to Mazda service center sorted the problem, but they don't mention what was the solution.
I took mine to Mazda service center and they had no idea how to fix this and what is causing it :(

Please, if anyone had an idea what needs to be done, share the solution.

So far I did:
1. Forced long regeneration of DPF (performed by Mazda personnel)
2. Checked all Diesel fuel injectors (all worked fine)
3. Used several additives cleaning DPF ( DPF ware factor reported by Mazda software is about 7% - excellent)

none of the above worked.
Your route & traffic will affect regen cycles. If trips are short & slow, DPFs get clogged faster.
Proper periodic DPF cleaning requires removal. I doubt the dealership would've done this on yours...
The permanent solution would defeat its purpose & would be cruel to Momma Earth...DPF Can surgery w/o touching the CAT & ECU reprogram...No dealership will ever do this for you.

Sent from my SM-G970F using Tapatalk
 
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