If you do not have a factory service manual, GET ONE! You can order one from www.ideal-z.com
. Their page will have a link to Courtsey Nissan, who will have the manuals. While at the Courtsey Nissan site, order the Ztherapy FI video. It too is a must have along with the FSM.
The info you need is in the engine fuel section... pay close attention to the air flow meter tests, water temp sensor tests. Other things to check in the engine electrical section is the ignition transistor unit and distributor and coil.
Be sure all the FI sensor connectors are clean! (not on the outside, but the contacts).
The FI Z's rarely have vapor lock. Most of the problems with stalling is crud in the tank/lines, bad FI sensors and wiring, bad transisitor unit or distributor.