Danny1, you're in Essex so you might be in the catchment area for one of the mobile guys on Disco3 - Geoff. (with the fullstop at the end of his username). He does travel (he did my TDV8 a few years ago in Oxfordshire) and is a top chap. He has the flush kit in his van and does it on your driveway. Recommended by all who have used him.  2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

Hi RRSTDV8
I will take a look around on the disco site for Geoff. Thanks!.
I have also emailed a transmission specialist in Hornchurch, I’ll see what they have to say?, I’ve asked if they do a diagnostic not a plug in as there is no codes present. Regards,

Danny