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Discussion Starter #1
I read an article in Aprils "Jaguar World", and it mentions in addition to resetting the service due message later models also need a oil dilution reset as well. I'm thinking an X250 with a DPF is probably considered a later model.

Has anyone checked if the oil dilution percentages are reset when you follow the service reset button sequence ( with fog light button etc ) ?

I'm thinking failed regen puts that percentage up, and the only thing reducing it is an oil change? In which case eventually if the calculated figure doesn't get reset when the oil is changed it's going to report an error / require an early service.
 

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I would imagine that a service reset would reset everything that the algorithm uses to calculate when a service is needed. So yes, I reckon it would have to, as inferred oil dilution is one of those factors.
 

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Discussion Starter #3
Yeah you'd think that, and it may well just be the commercial outfit giving the info to the magazine attempting to pull in more trade. Then again given some of their other design decisions you never know. I'm still stunned by the revelation that they make the wheel nuts in two parts, that can break apart!
 

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Discussion Starter #5
I think they call it "Oil quality fuel dilution factor", and i represents how much un-burnt diesel has ended up in the engine oil.
As far as I can gather the DPF regen works by injecting some diesel during the exhaust stroke, so it goes straight into the hot DPF, and burns the soot that has collected there. Somehow if regen is aborted some of it ends up in the oil, (forcing past the piston rings? Output to cold ( as you've slowed down) to clear the DPF so more back pressure? Just left in the cylinders when you switch off mid cycle? )

I wonder how soot gets in the oil? Perhaps via the EGR system if they have that on diesels.
 

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Some diesel from the exhaust stroke injection will always get past the pistons into the sump. Oil dilution is a " normal" thing. The problem arises when the DPF regen' constantly fails and the diesel injection goes on and on.
 

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Hi, never fill the oil past the half way mark between minimum and maximum, you can then see very early if the oil level begins to rise, this points to diesel in the oil. Phil
 
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I think oil dilution happens all the time. Fuel then vaporises and taken back to air intake. Active regen increases the rate of dilution because more fuel injected after the make combustion while it doesn’t have enough time to vaporise and burn. The furthur the DPF is, the more fuel is injected after burn and the dilution rate increases while vaporisation rate is almost constant. Now eif engine is shutdown before the process is complete the vaporisation will even slow down and worsen the issue.
 
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