Oil dilution

[MarkyD1977]

Let me explain

Peugeot 308 SW Gt line, 2.0 blue hdi 150, 71k miles

Recently I had a dispute with Peugeot dealer….long story.

Upshot is, ad blue injector replaced and DPF removed, sent away, professionally cleaned, all good.

I live on the Isle of Wight and this is not the place to own a diesel with a dpf. I frequently get the warning for possible clogging, find somewhere to get the revs up and it resets itself. No big deal.

Following reinstall of dpf some forced regens were done, few month later, service warning. Computer said oil dilution issue. Presumably as a result of the forced regens ? Maybe

Oil change done and then a few weeks later an MOT. Tester noticed oil level a bit higher than ideal despite recent service.

Assuming dpf in good order, Peugeot dealer said it was, why is my oil becoming diluted with fuel ? Is this likely a nox sensor issue or other ? If so, which one? Nothing obvious shows up on diagnostic.

Any suggestions clever folk?

[wheeler]

Yes forced regens are not ideal & i would always recommend an oil change after a forced regen.
The main cause of oil dilution if failed or interrupted regens. A decent diag tool should show you when the car last regened & the average distance between regens.

[MarkyD1977]

So it’s more an issue of short journeys and so on and interrupted regents than anything actually wrong with the car? Presumably once diluted the car doesn’t rectify this? Oil just fills until level sensor triggers a warning and it must be changed? Does the car monitor the oil quality or just the level?

[wheeler]

There could be an issue with the car that is causing the failed regens rather than just driving style.

Once the oil is diluted it must be changed.

Don’t rely on the car to let you know something is wrong, the first you may know about it is when the engine takes off on the oil & starts revving uncontrollably (even if you switch the key off).
This is why you must check the oil level regularly with the dipstick.