I was wondering if the Platinum Tipped NGK's were absolutely required and if misfires could occur if I installed some NGK's that weren't platinum tipped

 

Yes and yes. Some people (who heavily drag race) run NGK copper tipped, but they'll only last about a year before needing replacement (they run them as a precaution since the plug is more likely to blow out before detonation occurs).

The Z32's cylinder head was designed to work with NGK platinums. I suspect you didn't use these and are suspecting that's the cause of your misfire?

 

Yes and yes also! Thanks again zlover! You really are helpin me learn the odds and ends of this vehicle. Even though the sputter is intermittent I'll change to platinum tipped and see if that makes a difference. Although I'm not sure if the wrong spark plugs would make the check engine light come on because of a sputter?

 

It generally shouldn't cause a check engine light. Here's a writeup on how to pull trouble codes:
http://www.ttzd.com/tech/diagnostictech.html

Codes listed with a star can cause a check engine light. Might want to pull codes and figure that out before doing plugs (though I am certain that you're not doing any good by having the wrong plugs in the car - I'm serious when I say the motor was designed for platinum NGK plugs).

 

Thanks zlover, I'll go and do that. Well remember when I said my check engine light goes off and everythings normal and then it comes on and theres a sputter? Am I going to pull a code if the check engine light is not on?

 

Does that apply for the NA and TT?

 

Does what apply for NA and TT?


And regarding CEL codes if the light's not on - I'm not sure. If possible, do it when the light is on. I don't recall if it has memory to store trouble codes that are no longer active.