Especially when the air temperature is warm-hot, my 1988 RX-7 frequently falls below 750 rpm idle and stalls.
The most common occurance is after going freeway speed, breaking for a stop. It just goes down to zero as the stop is approached. Sometimes, it does not do this, and idles fine at about 750. I am a new owner, and the only guy in town that is normally excellent with all foreign cars is stumped. Notes: Replaced fuel filter, new plugs, otherwise, the engine runs fine. Please help! Thank you!

 

Take a look at the FSM manual if possible to familiarize yourself or just do a search in this forum.

Generally BAC may be bad or dirty if the RPM's drop upon electrical load such as A/C, lights, etc..