My Integra IS MISFIRING

ok so i thought it was the injectors but i guess not… wen i start up my car it runs fine. till it warms up and i start to drive it. then i misfires like crazy… wen drivin it stop misfiring above 3 rpms. it is cyclinder 3. the cyclinder is getting spark and the fuel injector is giving out fuel … does anyone kno wat this could be…