If the leads & plugs / injectors are OK ( you can check by taking the rail out and placing each injector in a jar, take dizzy off and spin dizzy with the engine ignition at run position (not start), each injector will fire. You can test spark/leads by unplugging lead and see if engine tone changes and then switch the plug/lead to another cylinder and see if the problem moves.
check the autodata files in the electrical FAQ and make sure your base ignition timing, co pot and idle screw is set appropriately, otherwise you will be chasing your tail