You know when the car is cold and you start it in neutral, it will rev for a minute until it warms up and then it will drop to a reasonable idle.

But if you start it when cold while in gear, it revs and drops to idle almost immediately.

Also, when a warm car is restarted, it doesn't do this high idle/lower idle routine.

What do you call that?

 

Normal operation for the car.
The high revs when cold are to heat up the pre cat quickly.

 

It's called the Accelerated Warm-up System. More info available in the factory service manual.
http://wright-here.net/cars/rx7/manuals.html

 

Well that's a handi website. I'm gonna bookmark that one.
And now I'm reading through the troubleshooting section...