I own a 91 LS400, my problem has happened twice. On extremely hot days running
the ac, cd & lites the engine will shutoff. I'm usually idling in stop & go traffic, any ideas?

even though this post is old, if any of u r having the same problem, maybe its bcuz ur using too much of the cars energy and there for the car compenscates and shuts down

noo

there has to be another cause if you used up all of the energy, once your car would die you wouldn't be able to start it up again...need more info..
did you get it solved???
if not post
any lights on?
how many miles??
any maintance done to it??
if so what kind??

to me what you are describing is a fuel problem or more likely then anything else.
it's ither the Ecm(engine control moduel) is not seeing that there is a lode put on the engine and dose not adjust the rpm idle or there is a fule problem or ignision problem that is not being adressed..
post back please