so i just found out that one of my secondary injectors was replaced with a primary injector and it cuts off at 3500k would the injector be the problem? also what is the number of the injector and the size if different

86 se

 

Yes they are unless they are aftermarket larger injectors.

See faq: https://www.rx7club.com/2nd-generation-specific-1986-1992-17/frequently-asked-questions-2nd-generation-rx-7-faq-fc-494667/

Your problem sounds like the common 3800 rpm hesitation, most of the time caused by bad grounds but if you are sure the one injector is the only one not firing then it is most likely bad. There are alot of posts on this issue here.

 

i noticed that one of the secondaries was cracked at the bottom i think this may be the problem to it