1991 Z32 N/A Ignition Issue

[xvt]

I am having some issues with my ignition. I think it is the number 4 cylinder (middle coil on driver side) does not ignite. I checked the plugs, coils and everything is fine. I did however check the wiring plug to the coil with a voltmeter and it first showed 14v, then dropped to 12v, now it's just dead.

I also checked the computer and shows no fault codes or anything. Interesting considering it's running on 5 cylinders.

I replaced my PTU with a brand new one today. Still not working! I am getting signal from the PTU but no positive voltage from the power wire.

Any ideas?