Mystery Smoke Problem Solved For A Tenner! VW 1.9 TDI PD

After almost a year of head-scratching between myself and two mechanics, I've found the source of the smoke from my 1.9 TDI VW Passat. And I'm so glad I didn't start stripping the engine down!
This car is a VW Passat B5.5, with an AWX motor in it, but this video should help if you have any 1.9 TDI PD with the same intermittent blueish smoke when you accelerate after engine braking or stop-start traffic (between a couple of minutes after start-up and full operating temperature).
Vorsprung durch versuch und irrtum.
© 2021 E.C. Adams
(Here's a great video - which I do not own or have any rights to - with the method for replacing the sensor: • VW fuel temperature se... )