It seems like the injector is having problems one of the cylenders is not firing and is has a los of power and seems to run rough what could be wrong

Look you are looking at a number of things when a Cylinder, it can be electrical,1 like the spark plug can be not working, 2 the distributor cap if the car has one, 3 The spark plug wire that runs from the distributor to the spark plug that spouse not to work, 4 The fuel distributor if the car has mechanical fuel injection,5 The injector it self, is a way to diagnose it by first identify which Cylinder is not firing, also can be a burn intake or exhaust valve, to find out that you need a compression test at that not working cylinder. 2A
NOW if Your car is electronic fuel injection it can be a defective injector or the computer, You can try by taping on that injector wile motor idles, good luck