first off, black on the plugs means RICH not lean... lean would be all gray/white from being burned. Black is suit and carbon that isnt burned off of the remaining fuel.
first i would check to make sure your plug wires are good and installed in the correct places.
Next i would make sure all the wires to the coil packs are connected. The 95 DOHC has issues with the ICM (ignition control module) basicly it is what the coil packs connect to. without it there will be no spark. because of the location below the exhaust and the heat there...they dont tend to last long. places like autozone for one can test these i have heard.
so if i understand you right, the engine is turning over, but no start. if that is the case and you already know there is an ignition issue then i would start there. wires, ICM, possibly coil packs...althought they rarely fail.
other issues to look into on any of the DOHC engines are:
-vac leaks. there are a lot of vac lines that can crack with old age and this engine doesnt respond well to them. also the lower intake manifold gaskets leak as well in time...
-a dirty MAF sensor could cause issues too... but not the issue your seeing.
-a colder Tstat. these motors do not like heat, a 180* thermostat isa very good idea.
96 MC Z34 (RIP LQ1 firstname.lastname@example.org) L36 email@example.com www.cardomain.com/id/z34phoenix
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