David and Mark,
Thanks for that insight. I was called to the car by a garage customer as a non-starter. It had logged 00542, needle lift sensor, which was indeed open circuit. Although I didn't think this was the cause for the non-start, it felt pointless to continue until such an obvious fault was rectified. They eventually fitted 'another' injector, and the code cleared, but still no start. Further investigation revealed no fuel at the filter. As the wiring diagram showed an electric pump, I naively assumed it to be a pressure pump, and my investigations went down that line. A case of incomplete knowledge. So, Mark, is my next test on the suction side of the filter head/pump, or is there another piece of VW wizardry waiting to trip me up?
TIA,
Peter