Every now and then I look at Ford Etis for my November 2015 Fiesta 1.5tdci. Today I see it mentions it needs 17E09 - 1.5L AND 2.0L DURATORQ DE-SULPHURISATION.  From using google, as far as I can tell this is a software update and something to do with the dpf regen.

Does anyone know

a) as car is out of warranty should Ford do this free of charge for me?

b) what is the result of not having it done. If not done, does every one of these cars suffer some bad result or will it only affect some people in some quite specific circumstances based on length of journeys, driving style etc?

1) It is a free PCM update provided by Ford and takes upto 30 mins to complete

2)Here is the official Ford dealer tech blurb:

1.5L & 2.0L Duratoq Diesel engine:
De sulphurisation PCM calibration - Emission Regulatory Program

Over time sulphur from fuel may
accumulate and the regularly initiated de-sulphurisation of the exhaust system
may be interrupted under certain driving conditions. Revised PCM calibration is
available to ensure continued de-sulphurisation.

It's basically for emission control more than anything, my ST needs this and was due to go in before the garages all closed, however it's not essential to everyday driving. If you have any custom PCM entries or remapped, advise the dealer of this first. They won't remap but if you've got certain features enabled that use the PCM then they *can* enable these again if they're friendly and know what they're doing.

This is an old recall, it's been going around for at least 3 years!  They seem to add more cars to it over time though.

Sulphur that accumulates in the exhaust creates SO2 (sulphur dioxide) emissions when cruising.  The de-sulpurisation is basically a hotter regen to burn off the sulphur regularly to keep the SO2 levels down.  

Nothing bad will happen without the recall, but it's worth having done imo.  I also wonder if they may have tweaked the regen procedure to reduce the rising oil levels due to regens in with this map...

thanks, I'm a bit undecided, it will probably end up with me not having it done just because that requires less effort than having it done. some type back, maybe 2 years I did have problem with high oil level but have not seen this more recently. When I do drive the car, most journeys are 33 miles (as I live 33 miles from work) and three quarters of that is fast constant dual carriageway/motorway. so it's not like the car is always being used in a way totally unsuited to a dpf diesel.