'87 Z31 Hot Start Problem
 

For any who still daily drive these old cars; first time encountering this issue_Haynes manual provided first clue; clogged air filter_used 125 p.s.i. to clean that up.
(The engine got to where it would not start hot at all_the C.P.U. was flooding the injectors with gas trying to make it happen_was having to wait for it to cool down a bit and finally start.)
The problem persisted_intuition said look at the distrubutor cap and rotor.
The cap contacts were black, had to use a pick to get the crap off somewhat, the rotor cap was bonded to the shaft, had to pry it off partially destroying it.
The entire assembly was coated with what looked like a light-reddish oil which a rag wiped away.
After cleaning, the engine started right up_IMPORTANT_disconnected the ground battery terminal overnight to clear out bad codes from the C.P.U.
Next afternoon drove the car to pick up a new distributor cap and rotor _ whatever chemical reaction occured inside the distubutor cap and rotor bonding to shaft, rendered these parts unreliable.
Engine could use a new set of spark plug wires, the Nissan set has been on it for at least 12 years_

• Hot start problem apparently resolved after day long road tests_engine starts normally regardless of temps