dieinobc

hey people feel free to answer this my rx7 91 is doing weird **** it runs but when i give it gas it will just shut off completely but when i touch the peddle slitly it will rev up to a bout 4 thousand rpms and then just drop, now i just bought this car for 300 dollars great deal but i put 4 hundred in for a new fuel pump and started but the only think it is missing is a cat converter on it so i was wondering if it had a co2 sencer on it or if the rotary engine has to have backpressure to run please reply thanks o and if you know what it is email me at dieinobc@yahoo.com thanx