Diesel in Engine Oil

Faults and Technical chat for the Mazda CX-3
mimiaris
Posts: 6
Joined: Tue Apr 02, 2019 8:56 pm
Location: Croatia

Re: Diesel in Engine Oil

Post by mimiaris » Sun Apr 14, 2019 4:39 am

Hi, I am Marko from Croatia. Please if you can send the dpf regeneration process from the fuse box .My email adress: markod1980@gmail.com


bogdanandronesterca
Posts: 4
Joined: Tue May 07, 2019 7:20 am

Re: Diesel in Engine Oil

Post by bogdanandronesterca » Tue May 07, 2019 7:25 am

Bought a used 2016 CX 3 1.5 diesel, 3 weeks ago with 107000km on the clock. Noticed that the oil was high to the X mark on the dipstick. On oil change I measured the oil that I took out and it was around 6.3 Liters(including the oil that i took out of the filter, more than 1 liter to much), and according to the label on the engine, last oil change was 8000 km ago. I think the car is doing a lot of silent DPF regeneration around 3 times a week since I-Stop not working and fan continue running after engine stop (no warning signs in the dash or in the main screen). Tomorrow it is scheduled for service diagnostic. Guess I will be needing new injectors and like people mentioned here before it is no guaranty problem will not come back. I am surprised that no factory recalls have been made for this problem. Expected more from a car that is less than 3 y old, good job Mazda... Will let you know more after the trip to the service.


bogdanandronesterca
Posts: 4
Joined: Tue May 07, 2019 7:20 am

Re: Diesel in Engine Oil

Post by bogdanandronesterca » Wed May 08, 2019 2:30 pm

The official Mazda Dealer did a full diagnostic on the car and said it is in great condition and has no errors. Told them about the oil going up on the dip stick and they said that the dilution is a common thing with the diesel engines which are not suited for short trips and I should monitor it and change the oil if it gets to the x mark, and "under no circumstances should be the car driven after the oil gets to the x mark which can lead to engine damage". They printed out a full Data Service Record of the car mentioned it had been recalled 2 times, one time for the pistons that hold up the tailgate and one time for the software update that was related oil dilution (update for injectors function, DPF regen, and others). Glad the the owner before me did the service on time...Still think that the diesel getting into the oil in such large amounts when the silent regeneration is interrupted, is caused by a pour engine design by mazda. Will monitor the level of the oil and let you know how it goes. Until now I did 700 km with the new oil and the mark it is ok on the dipstick. Dealer suggested filling the oil to the minimum mark on the next oil change, to prolong the overfilling from dilution.


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AndyRen
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Location: Down a bit, down a bit more, right a bit, down a bit.... Right there - Kent

Re: Diesel in Engine Oil

Post by AndyRen » Wed May 08, 2019 4:15 pm

I can't really help you, but fuel in the engine oil is a problem with all newer diesel engines with dpf's not just Mazda! Short trips are a major problem with the resultant failed regen's when the engine is switched off before the regen has finished.
16 plate 2L Petrol, 120bhp Soul Red Sport Nav...


bogdanandronesterca
Posts: 4
Joined: Tue May 07, 2019 7:20 am

Re: Diesel in Engine Oil

Post by bogdanandronesterca » Tue May 21, 2019 6:50 am

I have been monitoring when the car is doing the silent regeneration, so I don't interrupt the process and the oil has not been rising since. Does anyone know how I can speed up the silent regeneration process. Or maybe is it time based and it will stop after a period of time regardless of how many km you have done or how many revs/ speed you are driving at, since the start of the regeneration? On my last silent regen, after the process started, I drove around 7 min at city speed avg 35-40 km/h then I got to the parking lot and and accelerated with the car in neutral every few seconds. Did this for 10 minutes and still did not finish, so I figured maybe the wheels have to be moving... I moved the car 40 meters and the regen process was completed. Was it a coincidence that it ended when I moved the car? Did anyone managed to see the silent regeneration complete while the car is not moving but the engine was on?


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AndyRen
Posts: 449
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Location: Down a bit, down a bit more, right a bit, down a bit.... Right there - Kent

Re: Diesel in Engine Oil

Post by AndyRen » Tue May 21, 2019 9:03 am

I may be wrong but I think it's a bit more complicated than that, there are sensors covering all manner of engine/exhaust/DPF soot levels etc that may vary on a day to day basis dependent on engine temp, external air temp etc etc, so I don't think you'll ever get a proper result??

As I say, I may well be wrong? But when you notice the car doing a re-gen then continue to drive it for a while (time and speed I couldn't say though).
16 plate 2L Petrol, 120bhp Soul Red Sport Nav...


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