how can you tell if one rotor is not firing?
 

how can you tell if one rotor is not firing?
can a rotary engine run on only 1 rotor?

yes it can run on only one rotor and one chamber of the other rotor if an apex seal has blown. i dont know if you are asking if it may not be getting spark???? if that is the case, why not disconect the plugs and have someone crank it to see if there is spark. if asking b/c you think you blew it. get a compression tester.
how can you feel if it is running on one rotor? i dont know how to describe it to you other than it lacks power and you can hear a clunking/ banging sound from the bad chambers as the motor still sends fuel and spark , but it is not combusting corectly....i cant think of how else to describe.

Simple. if the car idles any worse with either leading plug wire off the spark plug, then the rotor that still has the wire connected is either not firing or has a blown seal of some sort, or no fuel.
Any engine requires three things to run: compression, fuel, and spark.

I explained the procedure here:
https://www.rx7club.com/vforums/show...threadid=11060