1996 4-Runner Stalling Problem

Hi,

I have a 1996 4-Runner V6 SR5 with about 150k miles on it. Thus far,
I've performed all major tune-ups at Toyota dealerships and intend to
bring it in this summer for another.

For the most part, the car still runs great and when the engine is cold
it starts up beautifully with no problems. However, if the engine is
warm and I turn the engine off (e.g. to run into a store or something),
when I come back and turn the car on again, the engine will start up
fine but then almost immediately idle back down to zero and stall-out
unless I press the gas pedal and force more gas into the system.

Again, this only happens when the engine is warm. Any advice on what
the problem could be?

Any advice would be greatly appreciated!