coil won't show up in ecu fault memory on mk3s. neither will injectors necessarily (may come up with a fuel adaptation error or similar).
coil will have a fairly high resistance and certainly output stage (where king lead goes on to) should have a high resistance in kOhm area to GND.
injectors will be low impedance, you're talking a few ohms, maybe up to few tens of ohms.
mind you both are inductive so they have a complex part to their resistance, I would imagine the input stage of the coil might even have a non-linear resistance because there might be a power transistor / semiconductor in there...