1993 Nissan Sentra XE 1.6 Lit. Automatic. Won't Start

I have a 1993 Sentra XE and having problems starting it.(Once in a while)… When
I try starting, I turn the ignition all the way to start but there’s no response.
All the light on the dashboard panel is all lit up but nothing happens, no
sound at all. I’ve changed the Neutral switch, the Starter, and Ignition relay(Grey
square) which is located at the fuse box engine side… sometimes it will start
and the car runs fine…smooth as a whistle… then when I re-start it again,
the same problem occurs…I have to wait for about an hour or so, then when I try
starting it again, it will start…I’m confused and it’s driving me crazy. I’m
afraid to drive the car on a long trip, I’m afraid it might not start at all… Can you
please give me some advice what to do next… by the way, the car battery is
good… Many thanks in advance…

Carolyn
(San Jose California)

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