Nissan xtrail 2.2 dci

[whatarascal]

Nissan xtrail 2.2 dci
Happy new year folks.
Last Feb I bought a Nissan xtrail and ran it throughout 2017 on my homebrew biodiesel.
At the beginning I noticed starting to be a small problem.I had to depress accelerator to get it to start first time.
I changed the fuel filter after a thousand miles
It ran great until November when it started ok but when asked to drive it would cut under load.
I changed filter and it was ok for another month then the stalling under load started again and would only drive when engine was up to more or less normal temperature.
I had done around 5000 miles on bio.
Its been to a diesel specialist who found nothing untoward other than a vacuum valve.
Any one on here had issues with this engine on bio.Any info will be most welcome.

[Julian]

Do you have a door step sample to check each morning?

Might be "stuff" (HMPEs) dropping out in cold weather if filter changes solve the problem for a while.

[whatarascal]

I will start to do samples,I stopped checking after I started centrifuging my bio.
Could not see ant wax in filter

[Chug]

sounds like fuel starvation or drawing in air, have you checked the fuel tank strainer for blockage?

[whatarascal]

yes strainer clear no air bubbles in the line