[tccrab]

If your Z is a 90-92 most probable cause is fuel injectors.
Been there, done that.
If your Z is a 93-95, could be plugs, wires, coils.

Start and warm up your car until in closed loop. Pull the plug wires carefully one at a time and listen to the sound of engine. The engine should stumble and miss and sound different when you pull a working wire.
When you pull a plug wire and the engine sounds the same, there's your miss.
Coil pack problems usually cause misses to come in pairs, so if you've got two cylinders that are missing then it could be a coil going bad.
It could still be fuel injectors.

Are you mechanical at all? Do you have a Helms manual?
We can help you figure this out, but it does take a little basic knowledge of engines.

TomC
'90ZR1 #792