Oil dilution problems on Focus 2017 Mk 3.5 1.5 litre durotorq 120 bhp engine

[Agile]

A friend of mine has this problem on his car.

He thinks it is a common problem on his model.

He thinks that it is related to the car's automatic procedure for cleaning the particulate filter!

But I am rather sceptical about this as there seems to be little information available on the internet.

Does anyone here have any strong views on this problem ?

 

[Burnerman]

If indeed this engine does use excess diesel to regenerate the DPF then it is a particularly bad thing, and has caused the demise of many a good motor....Mitsubishi and Mazda in my experience!
Diesel is an excellent solvent but a hopeless lubricant.
I'd be contacting Ford concerning this one, just to see if it uses this system.
John

 

[Lower]

A friend of mine has this problem on his car.

He thinks it is a common problem on his model.

He thinks that it is related to the car's automatic procedure for cleaning the particulate filter!

But I am rather sceptical about this as there seems to be little information available on the internet.

Does anyone here have any strong views on this problem ?

Your friend is right. The emission system tries to heat up the DPF by injecting excess fuel into the engine, some of which makes its way past the piston rings into the oil. If the engine continually fails its regen cycle then it keeps trying and you end up with diluted engine oil.

If you don't then change the oil you can end up with the engine running on it own oil and it self destructs.

 

[dishman]

One thing I have realised recently is that if you look in the service guide for most cars there are two interval types.

Normal use and arduous use.

What I have come to realise is that the majority of people, especially those driving modern diesels, probably come under the arduous use category.

It's a misleading name. It should be titled, mostly motorway, mostly town.

But, if you town drive with some motorway, to keep the engine and the DPF in good order, you need to increase your oil change intervals.

 

[Agile]

If indeed this engine does use excess diesel to regenerate the DPF then it is a particularly bad thing, and has caused the demise of many a good motor....Mitsubishi and Mazda in my experience!
Diesel is an excellent solvent but a hopeless lubricant.
I'd be contacting Ford concerning this one, just to see if it uses this system.
John

His Ford Focus does use the DPF cleansing system but he does not know when it does the regeneration. I thought it might give an indication.

He does about 80% of his mileage on motorways so I would not expect the DPF to get very blocked.

His engine has only done 66,000 miles.

There is a software update on the DPF system and he is having that does today. As well as a diagnostic check. Akthough it is not documented what that may cover, I advised him to get a compression test in case any cylinders have serious problems although it runs very smoothly and starts from cold well.

 

[Agile]

My friend tookhisFord to the main dealer for a free DPF software upgrade>

He had also agreed to a £190 but unspecified diagnostic check!

Well nothing was discovered on the dignostic test and they did not make any charge. And the test was done by a 30 y.o. female. He thinks it may have only been a quick OBD test although they wanted the car for two hours for it.

 

[dishman]

I find this guy an invaluable resource regarding DPF issues.

O'Rileys Autos

O'Rileys Autos strive to be the best YouTube Channel for Mobile Mechanic Car Repair and Diagnostic videos. Weekly uploads of real life Repairs and Auto maintenance plus Diagnostic videos specialising in diesel & petrol emissions fault repairs. Automotive Repair Tutorial channel Diagnostic...

www.youtube.com

Unlike many garages and main dealers, he actually tries to understand the root cause of the issue by looking at the live data and problem solving.

A few of his videos cover fuel dilution issues, this being one:

- although that one relates to a Vauxhall (Peugeot), it relates to other manufacturers too.

He has a few videos relating to fords and the 1.5 engine if you search his back catalogue.

 

[Avocet]

Yes, oil dilution is "a thing". As other have said, excess fuel injected during an "active" regen. It gets past the rings and dilutes the oil. (Which, (a Ford engineer told me), is also what kills wet belts). Generally, the regen will be "passive" (the engine management system won't have to inject extra fuel, because the DPF will get hot enough on a motorway. An "active" regen is when the extra fuel is injected (typically on engines that do lots of short runs and cold start). A "forced regen" (specifically initiated by a mechanic) should always be followed by an oil change.

Not all diesel engines use that strategy though. PSA diesels, for example, use an extra additive - Eolys, which goes in the fuel and lowers the temperature necessary for a regen to burn off the soot.