This video is about testing diesel injector leak off on a CRD style diesel injector rail. This is on a Vauxhall Zafira 1.7cdti A17DTJ but is the same on most modern diesel fuel injected cars.
Also, when you snap the plastic connectors as I did, replacing them and showing how to recover and solve this added problem!
Replacement injector leak off connectors and pipe:
https://www.ebay.co.uk/itm/-/18422698...

Diesel leak-off test kit:
https://amzn.to/3MylKj5