90' Intermittent power - Spark problem

[RSLyrick]

Understood, let's see if more people can advise on your issue. Otherwise, Marc is your best shot.

However, I'm wondering how a faulty ECM could lead to such erratic ignition behaviour...To my understanding the ECM is using a single wire to trigger coils with specific timing advance / retard. How could only cylinder #5 ignition control fail ? And assuming that this is the case, cylinder #8 would also fail.

Bad coil seems like a more resonable explanation (manufacturing issue, bad contact on side #5 ?).

When a single cylinder is affected I would target parts that drive a single cylinder (spark plug, spark plug wires, injector).

That tickles my mind...I'm very curious about what's wrong with your Z.

Did Marc say something about the air leak sound ?