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.
How did you get the injectors checked and who/where did you get them changed. I'm on a 66 plate and have seen a slow reduction in my regen intervals where it'll be between 90 - 125 miles currently depending on my drivingAll these posts about DPF filling fast. It is not the fault of the DPF, which is doing its job.
Excess carbon which blocks the DPF frequently is caused by bad combustion in the cylinders.
The likely culprit are the injectors as I believe there was either a bad batch of nozzles fitted to 2013-on, not sure on range of years, but I have heard up to 2016.
It is well known to Mazda local head offices, but not the dealers. They will try and replace sensors making money ach time it doen't work.
The following graphs might explain the change.
View attachment 286480 View attachment 286481 View attachment 286484
After an injector change readings chaned dramatically.
DPF still fills up requiring a regen but at circa 200 miles, not 28. Engine readings all taken via Forscan .
I'm in Manchester and I'm at 91000 miles now, I do around 16000-20000a year mostly motorway driving which is meant to be what these engines are built for which is why I've been surprised by the regen frequency. I've got the full license version of forscan, and I always monitor my regens making sure I never turn off the engine mid regen. Mazda changed an O2 sensor and cleaned it under warranty a couple of years ago as they found evidence of excessive carbon buildups. I've thrown a lot of money at mine doing the suspension, aero kit etc so I wanna run this car past 200000 miles like my old Corolla if possible so if it fixes the problem, I don't mind spending the moneyJPK, whats you total mileage?
I used my local Mazda dealership as a sensor kept coming up( see image with the code). They replaced it once on my dime, then it went again so they thought, so they replaced it on their dime, then it went again.
I would think the original sensor is probably ok. Don't let the dealership talk you into a new one, with fitting and diagnostics it will cost you £200 and thats not the problem, unless they can show you testing it and prove it ( which they probably cannot). The code will come up again, which is overfrequent regens.
So the SM said that cannot be right there must be another problem, he calls Mazdaeur Kent and they asked for a scan of my ECM, then a deeper scan pulling off allsorts of stuff that we haven't access to with Forscan. Then they wanted the injectors removing and and the nozzle tips iwo the holes photographing to proove the holes were elongating. From the photos I took with a DSLR on a tripod with remote release and focused to the limit of the 18/55mm lens , you still could not tell, though they did look a bit rough.
Eventually it was decided to replace them as they were not getting any better. Mazda Eur know about this but your average dealer hasn't a clue because they have no experience of fuel injectors nor the technology behind them. They just fit parts. They don't test injectors, no equipment ( which is speacialised and expensive) and neither have they the training to know what they are looking at or the time.
During my apprenticeship I learnt how to dismantle, overhaul the pintle and guide, reassemble and calibrate, also what to look for and test in a bad one. These were the old CAV type pressure operated injectors, not common rail solenoid operated types as fitted to most modern diesels now.
Where are you located? Any where near Newbury?
The other alternative is look for a fuel injection specialist that only deals with injectors and pumps and has the test equipment and know how.
If you are in this area
Head Office:
Feathers Diesel Services
Unit G12, Lock View,
Lowfields Business Park,
Elland, West Yorkshire, HX5 9HD
Feather Diesel Services Diesel Pump & Fuel Injector specialists
The UK's leading diesel injection system specialists with over 60 years experience. We inspect, test and repair diesel fuel pumps and injectors.www.feather-diesel.co.uk
They will know what they are doing, in fact Mazda used to use them , which just shows how much Mazda knows if they have to go outside to the experts.
Mazda does not show on their parts list a separate pintle a guide, only a complete injector. The injectors are made by Denso in Japan which is part owned by Toyota ( used to be wholly owned by them) and they make injectors for most Japanes cars, plus Vauxhaul and Ford.
Do you have an OBD reader and Forscan software?
A reader is about £20 and the Forscan Lite is about £4-5, down loaded to to a mobile device, be it a phone, tablet or even an old phone without a sim card which works as a tablet.
With that you cn see how many regens you have done over a certain number of miles. I check mine each time I fill up and take my fuel figures. Total mileage divided by regens from new is one way , but previous regen total from present divided into the miles covered will give you the mileage frequency. Ideal frequency is 150 - 200 miles, depending on type of driving. It looks like you are going through what I did.
Without Forscan you are really guessing.
It seems the problem only become apparent in the 40k mileage area and starts to drop off reall quick then as you approach 50, much like us really.
I paid £2.2 k for Mazda to do it, the expense is in the parts not the labour which is only about an hour to 90 minutes.
As I am planning on keeping the car it was worth me spending that money on it. Don't be persuded to take out the insurance, I looked at it and it was worded a bit vague as to whether you was covered. Selling it on is not very ethical giving somebody else the problem.
The thing is the problem is disguised, the car runs well, sounds good but fuel consumption suffers eventually as you can see from my graphs.
Keep in touch, there are a few cars coming up with the problem, three came up within a couple of months of mine happening, so my SM knew what he was looking at and what to do.
Both the SM and myself learnt a lot about this.
If you go to a Fuel Injection specialist they need to clean out your injector pockets, fit the latest new sealing washers that are tin coated then tighten them down to the latest specification that came out in 2017 I think.
Derrecky,Hi guys,
All from my experience:
I don't think that starting with injectors replacement is the best way to do it.
All DPF and performance issues are mostly due to carbon build up in the intake, which eventually may lead to injector failure (wrong air / diesel mixture)
I would start any diagnostings with EGR blanking and check regen frequency again. It is 10 minutes job, just some food can sidewall with 2 holes to match bolts (drink cans are not thick enough). It will show "engine icon" on the dashboard, but it make no influence to car performance during the testing.
Then I would clean up carbon build up in intake manifold + surroundings and sensors.
And just then start worrying about injectors - they are expensive compared to mentioned tasks.
Agree but injectors are not the only option.Javier, removing carbon on your intake system and the problems caused by faulty injectors are completely separate, doing either won't correct the others effect.
With a blocked intake manifold there is more chance of the dash lightingup like a christmas tree.
Wow that's some massive mileage. If it's not a typo that's 260,000 miles in 8 years! Are you still on your original injectors? Have you had the EGR, cooler or inlet manifold cleaned? Are you still on your original cam chain? If so that's pretty amazing!Hello, Just want to share my story if someone could find it useful. I have 2014 Mazda 6 driven now about 416 000 km and those kilometres driven mostly by me, so I have owned this car already for years and so quite familiar with it. The car has original DPF and never done anything (wash or clean or else) to it. Usually my interval between regens was between 240-400km, but about six months ago, it suddenly went to around 160km. I read this topic and decided to try replace the exhaust gas pressure sensor and so bought the latest improved version of that and replaced it by myself. (Same time I replaced vacuum pump as error code for it came 5 times within couple weeks, but this shouldn't have any effect on regen intervals.) I didn't reset any learned values of the gas pressure sensor after replacement. First I thought it wasn't helpful as didn't see any significant effect on regen intervals, but now after about 5 or more regens, the inteval has improved every time. Last one I had today was 330km and before that it was 300km so it seems it's getting better cycle after cycle. So, my point is that this sensor can be one reason for too short regen interval, but of course it can be something else as well.
You'd get a DTC and check engine light.What would happen if you either disconnect both rubber hoses to the differential pressure sensor or just the electrical connector?
Would this stop the sensor starting a DPF regen or would try and do one all the time? I suspect it would throw a DTC and warning light.
If it worked then the DPF regen would only be triggered after each time 17.1 litres of fuel have been consumed.