my rx7 will start but hit like 2000 rpms and will shut off and wont rev and then also it only starts some of the times but that i think is the fuel injectors are bad

 

I heard that over 2000 RPM the O2 sensor is used for the fuel mix... have you looked for any diagnostics? Any with a CPU have some sort of diagnostics to look at if you can get specs on where to hook up a light. What year is it?