Ignition knock box for an 85-87 GTI and GLI Golf / Jetta. Part number 811 907 397. This is a common swap onto 16v VWs, as it has a slightly more aggressive ignition map than their stock part, part number 811 907 397 E. Otherwise fully interchangeable.
I have no way to test this at the moment, but have no reason to believe this does not work as the car had a failed engine. No warranty implied, all sales final.