Wire to TD injector.

[paranoid]

What does the wire do that goes to the second injector do?
Noticed this afternoon a grey wire nearly rubbed through, the wire comes off the loom to a connector block above the first injector then a thinner wire goes to number 2 injector
Repaired it the best I could and I'm sure the hot starting problem isn't so bad now! Wondered what it controlled.

[Kowalski]

This is the injector needle lift sensor, it tells the ECU when the injector has opened, the ECU uses this so that it knows where the timing of the injection pump is so that it can adjust it to a specific value. The other sensor the ECU has is the TDC sensor (on the flywheel?), using a combination of the two sensors it can calculate what the timing advance currently is, this means that getting the timing adjustment of the injection pump is less critical than it might be.