Volvo V60 2013 D4 - random loss of power, no warning lights

[gman88667733]

I'd just filled up with V Power and gone into the dual carriageway today. After about 5-10 miles, the car lost all of its power, couldn't accelerate at all in 6th, then 5th and then eventually struggled in 3rd uphill to keep at 60. No warning lights at all.
This carried on for maybe 3-4 minutes and then the power came back fully and it was fine for the next 60 mile journey.
I'm at a bit of a loss as to what could have caused this? The car is high mileage at 155k, but it has a full service history and has been looked after.
To add, I have, since owning the car in July, noticed a fumey smell in the cabin at idle after a drive sometimes. I checked the tops of the injectors and 4+5 have a small bit of oily residue, but could have just been a drip from filling the oil up as the cap is next to them. The smell is the same as the smell from the oil filler cap if I take that off whilst the engine is running. Not sure if that could be at all related, seems unlikely.

I did think, maybe DPF regenerating as I'd really given it some beans a few miles before it happened. But I'm not sure that should sap almost all of the car's power.

Any ideas?

Edited by gman88667733 on Saturday 16th October 17:19