Apart from the 5 series and 3 series BMWs I had that I blew the engines of both then the Mk1 VW Scirocco remains the most unreliable car I've ever owned[and I've owned some real dogs
] As for the cranks sensor I don't know part numbers or anything but I'd suggest the post above by Enceladus is slightly off as my 3L was registered March 2000 and is the full facelift version and that has an oval connector.