ECU are expensive...don’t fire up the parts cannon just yet (shoot parts at problem, hope to hit target).

Are you certain that the injector for no.2 is firing properly?

Since that was disturbed during your work, I would be certain that the connection and injector for no. 2 work. I’m not certain if the ME7 needs to see a signal to the injector to send a signal to spark, but I know that the reverse is true: without spark, the injector signal is not sent by the ECU.

You’re missing the spark firing signal, I reckon.

Either the wire between the ECU and coil is broken, or the ECU isn’t sending the signal.

If the ECU isn’t sending it, either the ECU is defective, or, perhaps, it’s missing an input for that cylinder.

Check the injector.

Check that wire.